We examined the possibility that nonsocial, highly generic concepts are gendered. Specifically, we investigated the gender connotations of Arabic numerals. Across several experiments, we show that the number 1 and other odd numbers are associated with masculinity, whereas the number 2 and other even numbers are associated with femininity, in ways that influence judgments of stimuli arbitrarily paired with numerical cues; specifically, babies' faces and foreign names were more likely to be judged as "male" when paired with odd versus even numbers. The power of logically irrelevant numerical stimuli to connote masculinity or femininity reflects the pervasiveness of gender as a social scaffolding for generating understandings of abstract concepts. (Contains 1 footnote.)