Fatto generale: 10439 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 10439 is an unremarkable number.
Trivia: 10439 is an unremarkable number.
Data storica: July 30th is the day in 1965 that U.S. President Lyndon B. Johnson signs the Social Security Act of 1965 into law, establishing Medicare and Medicaid.