Fait général: 28231 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 28231 is an unremarkable number.
Culture générale: 28231 is an unremarkable number.
Date historique: April 16th is the day in 73 that Masada, a Jewish fortress, falls to the Romans after several months of siege, ending the Jewish Revolt.