general_fact: 17791 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 17791 is an unremarkable number.
trivia: 17791 is a boring number.
historical_date: September 15th is the day in 1958 that a Central Railroad of New Jersey commuter train runs through an open drawbridge at the Newark Bay, killing 58.