“Mike Tyson: Undisputed Truth” airs Nov. 16 on HBO.

For the heavyweight champion whose knockout punches all but left his opponents’ grandchildren limping, Mike Tyson comes off as surprisingly mellow and vulnerable.

The craziness that once swirled around him appears gone. His seersucker jacket is incongruous with the face tattoo, but Tyson is a study in unusual combinations, as revealed in “Mike Tyson: Undisputed Truth,” airing on HBO on Nov. 16.

Tyson, 47, slides his massive body onto a chair next to director Spike Lee for an hourlong exclusive lunch with Zap2it. They’re at a table in the back of a restaurant at the Beverly Hilton, where in wilder times, Tyson lived in a penthouse.

The film is a stage-to-screen adaptation of Tyson’s raw play, which had a limited Broadway run. In it, he doesn’t shy from uglier topics such as biting off opponent Evander Holyfield’s ear.

“I was just really p … ed off,” he says in the play. “I have the utmost respect for him. Please go buy his barbecue sauce.”

In person, he explains: “I don’t want this to be a redeeming story. I’m just a human being. Sometimes life kicks my a … . There were so many demons to get rid of. I would rather get high than have sex with a girl.

“We are very transparent, especially when you get to know somebody,” Tyson continues. “I have a different life than I ever had before. My exes look at my life and think it’s not real.

“You have to know what suffering and pain is.”

When the play opens, Tyson sits, silent. For a moment, one wonders if this is performance art. Tyson may be many things, but avant-garde isn’t one of them.

“Many of you are probably wondering what the f … Mike Tyson is doing onstage,” he says. “I wondered, too.

“Many thought this was my first time on Broadway,” he says. “It wasn’t. I was arrested on this same block.”

Had he not been arrested, he would not have been sent to juvie, met legendary trainer Cus D’Amato or, at 20, become the youngest heavyweight champion, Tyson says.

He’s unflinchingly direct and jokes about himself, how he needs a translator to be understood.

Tyson has taken speech lessons, and it is easier to understand him than when he was a kid with fists of iron and reduced most who dared step on the canvas against him to tomato cans.

Tyson learned early he could beat up people, especially when someone killed his beloved pigeons. Folks started setting up fights for him, but they had to bring opponents to him because his mother didn’t allow him off the block yet.

Make no mistake, though, Tyson was a thug. By the time he was 12, he had been arrested 38 times.

D’Amato trained him to channel his rage. D’Amato, a boxing legend, was the father Tyson never had, and Tyson had happy years in upstate New York with him.

“I looked like a fly in buttermilk up there,” he says.

But he’s a Brooklyn kid; he understands life happens on the street as the subway rumbles beneath. Part of the bond between Lee and Tyson is Brooklyn.

Lee recalls walking down DeKalb Avenue and Tyson pulling up in a Rolls-Royce for the premiere of “She’s Gotta Have It.”

Lee knew “Undisputed Truth” was a documentary the moment he saw Tyson do his one-man show.

“Because no matter how great a Broadway show is, once it’s over, it’s over,” Lee says. “There is no document of it, and people who couldn’t see it on Broadway can now see it in their living room.”

“I have never been around a human being as honest as he is,” Lee says. “The majority of human beings are trying to hide their imperfections, and to be naked and to bare your soul with some stuff that he is not proud of — that takes enormous courage.”

Tyson, a vegan, picks at bread but doesn’t order food. A few women walk by the table, and one flirts, asking if he remembers her. He grins and says he does.

The father of eight children, Tyson credits his third wife, Kiki, for everything he does right. They live in Las Vegas, and she helped him with the play.

During it, he talks about being convicted of rape and maintains his innocence. While he was imprisoned, Florence Henderson, Whitney Houston and others visited him.

In prison, he learned about Islam, lost his boxing license and discovered that his manager, Don King, was charging him $8,000 a week — for towels.

At one point, Tyson had close to half a billion. Then he was broke.

“I always wanted to be a guy who knew people, who knew everybody,” Tyson says, tearing off a piece of bread.

“Have you met Obama yet?” Lee asks.

“Before he was president,” Tyson says.

Whom does he still want to meet?

“Allah, when it is all a wrap,” Tyson says.