general_fact: 819 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 819 is the smallest number so that it and its successor are both the product of 2 primes and the square of a prime.
trivia: 819 is a boring number.
historical_date: March 29th is the day in 1867 that Queen Victoria gives Royal Assent to the British North America Act which establishes the Dominion of Canada on July 1.