general_fact: 19507 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 19507 is an uninteresting number.
trivia: 19507 is an unremarkable number.
historical_date: May 28th is the day in 585 BC that a solar eclipse occurs while Alyattes is battling Cyaxares in the Battle of the Eclipse, leading to a truce.