general_fact: 4017 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 4017 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
trivia: 4017 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
historical_date: December 30th is the day in 2006 that the Indonesian passenger ferry MV Senopati Nusantara sinks in a storm, resulting in at least 400 deaths.