Hecho matemático: 2291 is the number of inequivalent Ferrers graphs with 29 points.
Trivia: 2291 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fecha histórica: April 9th is the day in 1980 that the Iraqi regime of Saddam Hussein kills philosopher Muhammad Baqir al-Sadr and his sister Bint al-Huda after three days of torture.