General fact: 91237 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 91237 is a boring number.
Trivia: 91237 is an unremarkable number.
Historical date: October 18th is the day in 1945 that the USSR's nuclear program receives plans for the United States plutonium bomb from Klaus Fuchs at the Los Alamos National Laboratory.