Fatto generale: 2251 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 2251 is an unremarkable number.
Trivia: 2251 is an unremarkable number.
Data storica: February 28th is the day in 1922 that the United Kingdom ends its protectorate over Egypt through a Unilateral Declaration of Independence.