Hecho general: 612 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 612 is a number whose square and cube use different digits.
Trivia: 612 is a boring number.
Fecha histórica: September 3rd is the day in 301 that San Marino, one of the smallest nations in the world and the world's oldest republic still in existence, is founded by Saint Marinus.