general_fact: 12503 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 12503 is a boring number.
trivia: 12503 is an unremarkable number.
historical_date: March 25th is the day in 1807 that the Swansea and Mumbles Railway, then known as the Oystermouth Railway, becomes the first passenger carrying railway in the world.