Overview

1456 is a positive integer that can be considered both as an abstract number and as a year in the mid-15th century. As a year it falls in the late Middle Ages and is recorded in contemporary annals in Europe and the Mediterranean. As an integer it has several elementary arithmetic properties that place it among composite, even numbers with a modest factor structure.

Mathematical characteristics

In arithmetic terms, 1456 factors as 2^4 × 7 × 13. Because it contains an odd prime factor congruent to 3 mod 4 (7) with odd exponent, 1456 cannot be expressed as a sum of two integer squares. It is an abundant number: the sum of its proper divisors equals 2016, which exceeds 1456. The number has 20 positive divisors in total and its representation in Roman numerals is MCDLVI. In binary 1456 is written as 10110110000.

Notable events of the year 1456 CE

The year 1456 is best known for events that affected the security and religious life of Central and Southern Europe. In July 1456 a major defensive victory at Belgrade (also known as Nándorfehérvár) halted an Ottoman advance into Hungary and beyond; the defense was led by John Hunyadi and supported by a mix of local forces and volunteers. The victory had immediate political and morale consequences for Christian states resisting Ottoman expansion.

In the same year the papacy under Callixtus III reacted publicly to the Ottoman threat by calling for prayers and public acts of devotion. Traditions link the pope’s requests to the establishment of a more regular ringing of church bells as a call to prayer at set hours, a practice that later evolved into the daily Angelus bell in some places.

1456 also witnessed severe seismic activity in parts of Italy. Contemporary records describe destructive earthquakes in southern and central Italy that caused widespread damage to towns and infrastructure and are remembered as among the more serious seismic events of the late medieval Italian peninsula.

Context and significance

  • The military events of 1456 are often cited as a turning point that delayed Ottoman expansion into Central Europe for several decades.
  • The dissemination of printing technology, introduced a few years earlier in Mainz, continued to spread in this period; by the mid-1450s movable type was beginning to alter the production of books across western and southern Europe.
  • As a number, 1456 is a good example for elementary number-theory properties (prime factorization, abundance, representability as sums of squares) that are taught in basic courses on integers.