Fatto generale: 6219 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 6219 is a value of n for which 4n and 5n together use each digit exactly once.
Trivia: 6219 is an uninteresting number.
Data storica: January 9th is the day in 2005 that Mahmoud Abbas wins the election to replace Yasser Arafat as President of the Palestinian National Authority.