general_fact: 476 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 476 is the number of different products of subsets of the set {1, 2, 3, ... 11}.
trivia: 476 is a boring number.
historical_date: April 20th is the day in 1918 that Manfred von Richthofen, aka The Red Baron, shoots down his 79th and 80th victims, his final victories before his death the following day.