Hecho general: 16171 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 16171 is an uninteresting number.
Trivia: 16171 is a boring number.
Fecha histórica: April 9th is the day in 475 that Byzantine Emperor Basiliscus issues a circular letter (Enkyklikon) to the bishops of his empire, supporting the Monophysite christological position.