general_fact: 8247 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 8247 is an unremarkable number.
trivia: 8247 is an uninteresting number.
historical_date: July 30th is the day in 1978 that the 730 (transport), Okinawa changes its traffic on the right-hand side of the road to the left-hand side.