This number name first came to public attention when Erykah Badu and Andre 3000 chose if for their son, Seven Sirius Benjamin, born in 1997. Over a decade later, David and Victoria Beckham used it as their daughter's middle name, and now in these days of unisex word names, it's rising for both sexes. It's certainly one of the most name-like numbers: after all, it's only a letter away from Steven.

Seinfeld's George threatened to name his future child Seven, and then singer Erykah Badu actually did it.