Prince’s voice soared on stage — but he was also a behind-the-scenes humanitarian who once quietly donated money to the family of Trayvon Martin, the Rev. Al Sharpton said Thursday.

Sharpton recalled receiving a surprise phone call from the iconic singer in the wake of the 2012 shooting death of the unarmed 17-year-old in Florida.

“I will never forget when he called me and said he had some funds he wanted to give to Trayvon Martin’s family,” Sharpton said. “Just out of the blue. Just out of the clear blue.”

“He didn’t want anybody to know,” Sharpton added. “He didn’t even want Trayvon Martin’s family to know where the funds came from.”