general_fact: 47517 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 47517 is a boring number.
trivia: 47517 is an uninteresting number.
historical_date: February 4th is the day in 960 that the coronation of Zhao Kuangyin as Emperor Taizu of Song, initiating the Song Dynasty period of China that would last more than three centuries.