general_fact: 20908 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 20908 is an uninteresting number.
trivia: 20908 is an uninteresting number.
historical_date: March 29th is the day in 1500 that Cesare Borgia is given the title of Captain General and Gonfalonier by his father Rodrigo Borgia after returning from his conquests in the Romagna.