I feel like Umbrella was the biggest hit, but I feel like Bad Romance is more iconic and more remembered. Perhaps because Rihanna has had so many huge career hits since Umbrella it sometimes feels less huge than it really was.
Umbrella spent 10 weeks at #1 on Mediatraffic. Bad Romance 5.
Umbrella spent 7(?) weeks at #1 in US. Bad Romance failed to reach #1.
Umbrella spent 10 weeks at #1 in UK. Bad Romance? 1-2 weeks I guess.
Umbrella was #1 most successful song ww in 2007. Bad Romance #7 in 2010.