Top of the crops: Michael Bolton on critics, crooning and why the mullet had to go

He was famous for power ballads and that hairstyle – to the derision of some. Now Michael Bolton is a humanitarian with a short-back-and-sides. But will our interviewer ever get a word in edgeways?

I meet Michael Bolton – 'Grammy-award winner' and 'humanitarian', but never 'crooner' or 'soft-rock balladeer' according to the instructions to TV producers that somehow got caught up in my own press bumpf – at a London hotel and the first thing that strikes me is how small he is. Not tiny. He couldn't sit under a mushroom, for example, or crawl in through your cat-flap. But I had expected him to be a strapping, imposing fellow – probably, I now realise, because his songs are so brilliantly anthemic and huge and chest-beating, I was thinking of Tarzan. But he is actually fine-boned and petite.

"You're so much smaller that I expected." I even gasp, so he says: "Feel my bicep". I feel his bicep. It is nice, bulging, rock-hard, probably humane. "I watch my weight," he says. Sometimes, his remarks are only connected to my remarks tangentially, which is interesting, or is this just something that happens? When you win a lot of Grammys? (I don't know! I've never won any!)

He is 50, and beautifully dressed as you would be, I suppose, if you'd sold 53 million albums. His suit is Prada and divine – "Thanks. I really like it" – and his watch is a monster, the size of a dinner plate. "A Breitling Emergency," he says. It was invented by pilots, he explains. He points to the winder: "See this? It's an antenna, if you unscrew it. You pull it out and it starts sending an emergency signal. But there's a fine if you do it falsely or as a hoax." Handy, I say, but expensive, I bet. "It was," he says, "given to me as a gift by some very dear friends who are security-conscious."

And his hair today? Smashing. Short, tidy. He used to have extremely bad hair. You know, that mullet or, as they say in America, "business in the front, party out the back". But it was cut off in 1998, and auctioned for charity, the thought of which, I tell him, gives me the creeps, a little. It doesn't creep you out, I ask. That there's someone out there who owns your hair and who might, for all we know, take it out when sad and put it across their knee and repeat "Michael's hair, Michael's hair" while stroking it, perhaps in the manner of Blofeld and his white cat?

He says he knows the successful bidders. "A couple of women fans chipped in together for it, which was very generous. I think it was $6,000." He then says: "The most ever paid for hair was for John Lennon's hair, from a hair cut of his, and it was $7,500." If I'd known that, I'd have held out, I say, but weight for weight, your fans got the better deal, right? "It was a big bag of hair," he confirms. And when it was cut off, were you like Anne Hathaway in Les Misérables? Were you all howls and snot and dribble? He goes off on one, tangentially – I can now see this may be more because he's quite a stickler for the facts – and says: "My assistant and stylist were collaborators on my haircut because they knew I was thinking about it and they both wanted me to get it cut". Fair point, well-made, non-crooningly.

We are here to talk about his autobiography, The Soul of It All. In the introduction, he describes it as thus: "This book is about the soul of it all, which includes the deep emotions and vital forces experienced in a lifetime spent developing gifts and pursuing passions". It has been endorsed by Bill Clinton: "We all know that my friend Michael Bolton is a gifted musician and a devoted philanthropist – but you may not know that he's also a talented storyteller. This is the fascinating journey of a man who is as powerful, bold, and soulful as his voice".

Michael is a fabulous name-dropper, which is great because I love a name-dropper, and he has possibly earnt the right. He has worked with Pavarotti, Cher, Barbra Streisand, Bob Dylan, Ray Charles, Lady Gaga, Percy Sledge, Jay-Z. But this stickler thing he has for facts, combined with the name-dropping, can mean his answers are rather full.

When I ask him if his success feels real or if, when walking down the street, he ever brings himself up short by thinking, 'Hell's bells, I'm so rich and famous!', his way of saying 'It's all relative' goes like this: "I sit at tables at events with billionaires. They fly me into their events on their private jets, that they own. When I'm touring or doing a lot of functions or performances or studio work, and I have to fly into a place that is difficult to get to, I'll charter a jet so I'm able to do that performance, then get to another city, because there is no other physical way to do it, or because it's too taxing to then deliver what I'm going to deliver, like an 8pm performance. But these people own these jets; multiple jets, in different sizes.

"I was at a dinner once with Tommy Mottola, president of Sony at the time, and we were sitting with Michael Milken [financier and philanthropist] at an event for prostrate cancer. I've sold millions of albums. Tommy is president of the company and had renegotiated his Sony deal every year upwards. But he leans over to me and says: 'I feel like a fucking bus-boy at this table'. I knew what he meant, because we were sitting at the table with the CEO of General Electric and all these Fortune 500 companies who flew in by their own private jets to be there. And that was just our table. There were a hundred tables.

"I giggled when Tommy said that. And as Julio Iglesias once said to me: 'You can't buy these things with money from the music business. You have to buy zis and you have to buy zat'.' He was basically telling me you diversify, go into other businesses, then you own private jets, if you want to live that way. But I'm not interested. I'm seriously disinterested in it."

He was born Michael Bolotin in New Haven, Connecticut, to a Jewish family, and grandparents who had all immigrated from Russia. One of the curious things that struck me about his family, from reading the book, is that his parents didn't seem to have the usual Jewish immigrant mentality: didn't push education on their children in the hope they would succeed as lawyers, doctors, dentists and so legitimise the family's presence in a foreign country.

His mum and dad, Helen and George (a local official), didn't seem that bothered whether he attended school or not, and when he was expelled from Hebrew school, for not taking it seriously enough, they weren't that bothered either. "And you wouldn't have been able to go home after that, right?" he says. Too right, I say. He says his parents had too many other things going on to get on his case. "They were up to their ears," he says, "in their own personal problems."

The Soul of It All is as much about its omissions at its admissions. He hints at his parents' troubles, but does not specify, and won't specify now. What were their problems exactly, I ask. "I think they were both a handful for each other and I think they found themselves over their heads in so many ways." A sister is mentioned early on in the book and then disappears. How so? "I love my sister but she's had some hard times," is all he will say. When Bolton divorced his wife, Maureen, their three daughters came to live with him, but he never says why, so I say: why? "I will say that… it was a mutual agreement to try it out and it succeeded. For me it succeeded because 20 years later the girls were still living where I was living. I don't have a negative thing to say [about Maureen] and nor will you see one written."

He can be a total mensch, I think. And, also, he can be a card. He appeared on Saturday Night Live, parodying himself in a Jack Sparrow skit which, according to the directives to TV producers, can be mentioned, along with the fact 'It's had 100 million views on YouTube'. He can joke, too. When I ask him if he's ever been indiscreet with groupies, he says: "Two nights ago at this hotel I had five women banging on my hotel door until 3am". Gosh, really? "So I finally got up and let them out!" We laugh. He then says he told that joke a couple of years ago when he appeared on Loose Women, and it went down very well then, too.

He actually signed his first record deal at 16, but didn't have a hit until he was 35. There were hard times in between. "I will never forget having a landlord who was a really nice guy, but we lived in a duplex. One house, two different living quarters. And he had his in-laws in the other part of the house, and was carrying them financially. It was his wife's parents from Italy. Really nice people, couldn't speak much English. So I had a landlord tying to explain to me that he was sorry, he couldn't accept one more cheque that was going to bounce. He couldn't carry us all any more. So that was my closest experience of homelessness. It wasn't called homelessness then, but we were being evicted, as nicely as a person can do it." So you were evicted? "No." No? "I signed a publishing deal and started doing jingles. So, around the end of the month, when we were supposed to leave, we wound up moving to a much bigger house, and never looked back."

Still, nearly being evicted eventually led him to his humanitarian cause, Michael Bolton Charities, which assists women and children at risk from the effects of poverty, including abuse and violence. Here is how he tells it, in his own particular style. "When I started having success in '87 and being invited to all these posh, lavish events… beautiful ballrooms, where everyone took great pride in every setting on the table. I didn't know why they invited me until I realised celebrity is our world in the States. Michael Ovitz [founder of the Creative Artists Agency] once told me we don't have royalty in America, we have celebrity. It's how we raise money. It's how we bring attention to our issues of concern. We show up. Sometimes I would go, and Whitney Houston would be one of the artists, and Ray Charles. So I realised, while I was backstage at one of these events, I should be doing something in my home state, Connecticut, so my first intention was to help people who were struggling financially because that was the single worst memory through the coming years."

He has achieved much, for sure, but never critical acclaim. Can he explain this? "I was warned by a fierce critic, a friend of mine, that it was coming after Soul Provider [in 1989]. Soul Provider took me from 400 albums to 10 million albums, and I suddenly became a huge mainstream success, and critics don't like mainstream music. They like to find it, discover it, and help create the success." Hurtful? "I no longer," he says, "feel I'm engaged in a battle to win everyone over."

His personal life? Aside from his marriage, which ended after 15 years, his only long-term relationship seems to have been with Nicollette Sheridan, of Desperate Housewives fame. They've dated twice, in fact: between 1992 and 1995 and again between 2005 and 2006. He is vague about this in The Soul of It All and vague about it now. Both too busy. Never spent time together. That sort of thing. However, I did learn, from the book, that they're both mad for Scrabble, and I further learn here, now, today, exclusively, that he has a special Scrabble bag. "It's a bag given to me by one of my background singers as a birthday gift. In this bag, I keep the scores in it, and you can fit a travel Scrabble and the official digital dictionary, because you have to have the official digital dictionary."

Do you play now? "I'm not playing now. It's closely associated with Nicollette." Couldn't you and Nicollette just get back for the Scrabble? I know of relationships built on less. "Wow! Really? When I was out in LA, we would get together and have lunch and a game of Scrabble, even when we weren't seeing each other, which is a bit strange, looking back. We enjoy the game, but play competitively, and the score would always go into the bag." He says some of Nicollette's scores (in the bag) go back 15 years, which he knows, "because they are dated". I am rather touched.

But time is nearly up, so one more question. If someone had never heard a Michael Bolton song, I ask, and you could play them one thing, what would it be? I am awarded one last, beautifully comprehensive answer. "It would depend," he says, "upon whether it was more important for me to play a song I wrote or a song they would know and be more inclined to like. The male response to 'When a Man Loves a Woman' is much more friendly than the male response to 'How Am I Supposed to Live Without You', which they consider a more female-friendly song. But 'How Am I Supposed to Live Without You' is one that I'm more personally proud of, because I am one of the two composers on it, and it's been played over three million times. It's a copyright. It's achieved standard status. But if I sing a line of 'When a Man Loves a Woman' you'll know it's me, as compared to the Percy Sledge version, which even I considered definitive as a kid and…" And? "…which I eventually got to sing with Percy! It would be one of those two."

And now it is time for the photographs so he wanders off in his Grammy-award-winning way which, now I think about it, may be just that little bit humanitarian, too. Bless.

'The Soul of It All' by Michael Bolton (Sphere)