1139

1139 is an odd composite number. It factors as 17 × 67, making it a semiprime.

In mathematics, 1139 is not a prime or a perfect square. Its hexadecimal representation is 0x473 and its binary representation is 10001110011. The sum of its digits in base 10 is 14, giving a digital root of 5.

As a year, 1139 CE falls in the middle of the 12th century. Notable events include the Second Lateran Council, convened by Pope Innocent II in Rome at the Lateran Palace, from April 21 to May 17, 1139. The council issued decrees aimed at church reform and discipline, addressing issues such as clerical conduct and anti-simony measures, and it reinforced the authority of the papacy in governance of the church.