Alicia Keys and her hip-hop producer husband, Swizz Beatz, are looking to unload their luxury penthouse on Crosby Street for $17.9 million. The duo bought the lavish SoHo condo in 2010 for $14.5 million from Lenny Kravitz. (The rocker had the apartment — which has also played home to Nicole Kidman and Denzel Washington — on the market for eight years before Keys locked in a deal.) The 6,167-square-foot triplex has 3,000 square feet of terrace space, five bedrooms, four baths, four “powder rooms,” a “state-of-the-art windowed gourmet eat-in kitchen” and “formal dining room . . . encased in a glass solarium,” according to a Sotheby’s listing. And a “floating glass staircase” leads to a “private master suite complete with spa.” There’s an “automated entertainment system” and home theater, plus a wine cellar. Pictures posted of the pad reveal portraits of Keys, Sade, Muhammad Ali and Keith Haring art on the walls, and a Ducati motorcycle parked inside. Keys’ rep declined to comment.