Fatto generale: 17639 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 17639 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 17639 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: April 16th is the day in 1919 that Gandhi organizes a day of "prayer and fasting" in response to the killing of Indian protesters in the Amritsar Massacre by the British.