It takes a lot to be Rihanna, namely a truckload of Benjamins to keep her tresses looking oh-so-glam. According to a RiRi insider, the pop star drops a cool $22,000 on her hair each week.

The Daily Mail reports that the 23-year-old singer is shelling out approximately $3,250 per day for the services of top celebrity stylist Ursula Stephen. "Rihanna likes to pioneer new styles but it’s costing her a fortune," a source close to the singer says. "She makes several public appearances a week, and the cost soon stacks up."

The insider also claims that Stephen is a "close confidante" of the 'Man Down' singer, and they spend a lot of their time together. "You have to wonder why she insists on keeping such an expensive member of her entourage on the payroll 24/7," the source continues. "Most of these costs are paid for by her management."

Rihanna has changed her hair numerous times since her bright red debut last year -- 13 times according the Daily Mail article. Recently, the pop diva was snapped with a highlighted, chestnut brown 'do while sporting an itsy-bitsy, teeny white bikini in her native Barbados.