As if their music wasn't mind-numbingly catchy, both Katy Perry and Rihanna have smokin' hot looks to back them up when and if their talent fails. The spectral-haired starlets (who currently both sport jet black locks) both made GuySpeed's list of the Most Mind-Numbingly Hot Women of 2012.

Katy Perry, 27, clocked in at No. 12, while Rihanna, 24, was way up at No. 5. Both Perry and RiRi, in addition to being stunningly gorgeous, are record breakers. Perry is the only artist ever -- ever! -- to spend more than 52 straight weeks in the Billboard Hot 100, while Rihanna is the top-selling digital artist of all time, moving 47,571,000 singles as of 2012. Pretty impressive, right?

What's cooler is that the girls are BFFs and friendly rivals. Perry recently tied RiRi's Billboard record for the most No.1s on the Mainstream Top 40 chart. They each have nine chart toppers, and Rihanna'a list includes 'S+M,' which is on our list of the Top 10 Sex Songs. Ow ow!

This isn't the first time the pair have ranked on a hottie list. Perry and Rihanna nabbed the respective No. 1 and No. 2 spots on cheating site AshleyMadison.com's 'Hall Pass' list, meaning they're the two famous femmes men would most love to cheat on their partners with. We think their GuySpeed ranking is a bit more flattering, though.

Congrats to the two hotties!

Watch the Rihanna 'S+M' Video

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