Hecho general: 9219 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 9219 is a value of n for which |cos(n)| is smaller than any previous integer.
Trivia: 9219 is a boring number.
Fecha histórica: March 28th is the day in 2005 that the 2005 Sumatra earthquake rocks Indonesia, and at magnitude 8.7 is the fourth strongest earthquake since 1965.