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It’s less than an hour before Christopher “Ludacris” Bridges is scheduled to hit the stage with Justin Bieber at The Apollo Theater, but his mind is miles away from music. Lounging on a dressing room countertop in a t-shirt and jeans, he’s gazing intently at the pair of sleek headphones in his hands, which just happen to bear his name—Soul By Ludacris.

“I rap at least once a year that I’m on one of the FORBES lists, and that’s a great thing,” he says. “This is part of the reason, this here.”

For the versatile Ludacris, “part of the reason” is certainly the right phrase. He’s one of the most diversified artists on this year’s Hip-Hop Cash Kings list, ranking No. 10 with $12 million in earnings over the past year, pulling in cash from those Soul headphones, a cognac line called Conjure, voiceovers for RadioShack, music sales, roles in films including Fast Five and New Year’s Eve, and other ventures.

Ludacris is also one of hip-hop’s most consistent earners. Since his 2000 major label debut, every one of his seven studio albums has sold at least 500,000 copies. He’s made the Cash Kings list in each of its six years, racking up $80 million over that period—more than T.I. or Eminem. And he’s showing no signs of slowing down.

--“When we talk about building brands, we’re not in it for the short run,” he says. “It’s not about getting in and hurrying up and trying to sell something … We get offers all the time; that doesn’t mean we take every offer that comes to us.”--

Some readers might be surprised to hear that sort of talk from an artist whose oeuvre includes songs like “Move Bitch (Get Out The Way)” and “(You’s a) Ho.” But for Ludacris, who was studying for a degree in business management at Georgia State University when his career started to take off, that’s just part of the dichotomy.

“It’s almost the same as someone working in an office building from nine to five, and then on the weekends they go partying,” he says. “Every human being has different sides to themselves, and they showcase their emotions in different ways … I’d be doing fans a disservice if I only showed one side of myself.”

Ludacris got his start showing both of those sides at an Atlanta radio station, where he began as an intern and by the late 1990s had launched his career as a radio personality, using the name “Chris Lova Lova.” He also had an affinity for rhyme, but couldn’t convince anyone to sign him at first.

So from 1998 to 1999, Ludacris recorded and independently released his debut album,Incognegro, launching his own label, Disturbing Tha Peace, with his managers Chaka Zulu and Jeff Dixon. The album sold tens of thousands of copies—many from the trunk of his own car—more than enough to earn the attention of the major labels.

“Nobody believed in Ludacris, so Ludacris put out his own album; you can’t get more businessman than that,” says Kevin Liles, the former Def Jam President who eventually signed the rapper. “He’s engaging, he’s personable. That right there was part of his foundation to be in different businesses. Because to be diversified in business, you have to be a diversified person.”

Once ensconced at Def Jam, Ludacris’ career continued to soar. His first studio album, Back for the First Time, sold 133,000 copies in its opening week in 2000, eventually moving more than 3 million units. His second, 2001’s Word of Mouf, performed twice as well out of the gate and would go on to sell nearly 4 million copies; his third, Chicken-n-Beer, debuted with sales of 429,000 in 2003 and also went on to gain multiplatinum certification.

That same year, he launched his film career in earnest with a lead role in the car racing flick 2 Fast 2 Furious (he’d go on to star in four more installments of the series and is set for a yet another). After he picked up an Academy Award as part of the cast of Crash in 2004, it had become clear that he was more than just a rapper—and corporate partners have taken notice.

“He gets it,” says Dixon, who still manages Ludacris along with Chaka Zulu. “I don’t have to sit there—he can go talk at the correspondents’ dinner. He’s just a great pitchman.”

In recent years, Ludacris added Soul By Ludacris and Conjure cognac to his portfolio, taking a small equity state in the former and half of the latter. And then there was his guest verse on Bieber’s breakthrough hit, “Baby,” which has since racked up more than 750 million YouTube views, more than any other video in history (Ludacris politely declined to give specifics on what sort of royalties he gets, saying only that they’re “non-stop” and “continuously flowing.”) Next up: A new album, Ludaversal, due out this fall.

“I traveled the world over the last two years, I got to see a lot of things and had a lot of experiences,” he says. “That’s what Ludaversal is all about. Really kind of being vulnerable and letting you into my life … People are definitely going to understand a lot more about the personal side of Chris Bridges when they hear this album.”

In the meantime, Ludacris is trying to pass along the entrepreneurial torch. He’s helped his daughter, Karma, start an educational website (“She’s the CEO at age 10,” says the rapper, who owns the site himself). On the site, youngsters can hear stories about Karma’s interplanetary detective agency, play carnival-style math games and listen to science-themed songs like “Spacetacular.”

Still, on a night when he’s the featured artist for an even better-known headliner, Ludacris is reminded of another reason he’s earned his daughter’s admiration.

“Her father is a hero because he’s Ludacris,” he says. “But I’m damn near just as much of a hero because I’m on a song with Justin Bieber.”

As diversified a dad as he is a businessman, that suits Ludacris just fine