It shouldn't come as a surprise to anyone that RIHANNA enjoys the occasional reefer cigarette. But her friend KATY PERRY kind of called her on it in an interview with "Elle Canada". She said, quote, "I think Rihanna always looks so fresh and I'm like, 'How do you do that? We all know how much pot you smoke!' And you don't sleep because you're on Instagram at 4 o'clock in the morning!" Speaking of these two . . . Katy's new single "Roar" just hit #1 on the "Billboard" Pop songs radio airplay chart. That means that Katy and Rihanna are now tied for the most number ones in the 21-year history of that chart. They both have 10.