general_fact: 576 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 576 is the number of 4×4 Latin squares.
trivia: 576 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
historical_date: July 29th is the day in 1793 that John Graves Simcoe decides to build a fort and settlement at Toronto, having sailed into the bay there.