general_fact: 7770 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 7770 is an unremarkable number.
trivia: 7770 is a boring number.
historical_date: April 9th is the day in 1937 that the Kamikaze arrives at Croydon Airport in London – it is the first Japanese-built aircraft to fly to Europe.