1171

1171 is a natural number that comes after 1170 and before 1172. In mathematics, 1171 is a prime number, meaning its only positive divisors are 1 and itself. It is odd and not divisible by 3 or 9, since the sum of its digits is 10. In common numeral systems it is represented as 1171 in decimal, 0x493 in hexadecimal, 0o2223 in octal, and 10010010011 in binary. In Roman numerals it is written as MCLXXI.

1171 may also refer to the year 1171 CE, a date in the High Middle Ages. The year falls within a period of ongoing Crusading activity in the Levant and Iberia, as well as ongoing political consolidation in various European kingdoms. In East Asia, the Song dynasty governed parts of China while neighboring states and nomadic powers influenced regional affairs. Across regions, rulers faced the challenges of governance, religious authority, and inter-state relations characteristic of the era.

As a calendar year, 1171 sits within broader medieval historical narratives and overlaps with several regional developments typical of the period, including feudal dynamics, diplomacy, and military campaigns that shaped the political map of Eurasia. The number itself also has utility in technical contexts such as numbering systems and cataloging, where it serves as a discrete identifier or label.

In summary, 1171 denotes both a prime integer with specific base representations and a year in medieval history, linking numerical properties with a slice of historical chronology.