general_fact: 23990 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 23990 is a boring number.
trivia: 23990 is a boring number.
historical_date: September 5th is the day in 1991 that the current international treaty defending indigenous peoples, Indigenous and Tribal Peoples Convention, 1989, came into force.