math_fact: 4872 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
trivia: 4872 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
historical_date: May 3rd is the day in 1963 that the police force in Birmingham, Alabama switches tactics and responds with violent force to stop the "Birmingham campaign" protesters.