umbrella is really more remembered than any song by Beyonce globally. Umbrella the word is kinda synonymous with Rihanna now. heck, some guy was singing about it here just because someone said the word umbrella. that hook is timeless whether you like it or not.
Personally, i feel like it's a tie. They both have INCREDIBLE discographies that any artist would be jealous of. I still jam to old songs by both of them, from time to time.