math_fact: 17421 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
trivia: 17421 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
historical_date: September 11th is the day in 1982 that the international forces that were guaranteeing the safety of Palestinian refugees following Israel's 1982 Invasion of Lebanon leave Beirut.