general_fact: 61864 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 61864 is an unremarkable number.
trivia: 61864 is an uninteresting number.
historical_date: May 17th is the day in 1902 that Greek archaeologist Valerios Stais discovers the Antikythera mechanism, an ancient mechanical analog computer.