Fait général: 5243 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 5243 is an unremarkable number.
Culture générale: 5243 is an unremarkable number.
Date historique: May 9th is the day in 1964 that Ngo Dinh Can, de facto ruler of central Vietnam under his brother President Ngo Dinh Diem before the family's toppling, is executed.