general_fact: 15757 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 15757 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
trivia: 15757 is an unremarkable number.
historical_date: February 20th is the day in 1965 that Ranger 8 crashes into the moon after a successful mission of photographing possible landing sites for the Apollo program astronauts.