Dr. Dre could become the world's first billionaire rapper if Apple goes through with its purchase of Beats Electronics, the headphone maker co-founded by the hip-hop star.

Andre Young, aka Dr. Dre, is ranked second on Forbes' list of the wealthiest hip-hop artists of 2014 with an estimated wealth of $550 million. But if Apple's acquisition gets the green light, it could propel him to the number one spot, surpassing Sean Combs, aka Puff Daddy, who has a net worth of $700 million.