Hecho general: 1812 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 1812 is the number of fullerenes with 60 carbon atoms.
Trivia: 1812 is an uninteresting number.
Fecha histórica: December 16th is the day in 1922 that President of Poland Gabriel Narutowicz is assassinated by Eligiusz Niewiadomski at the Zachęta Gallery in Warsaw.