Katy could, especially since she could very well by the end of 2014 have 3 more #1's (not including DH). Rih obviously when she released though will have the lead single go #1. If the era is handled properly maybe another #1. Maybe. If not then I expect Katy to have 12 #1s and Rih 14.
Well Rihanna has been around for longer than Katy, it's impressive that Katy is so close after only a few years in the business. I think she will overtake her eventually.