263

263 is a natural number that comes after 262 and before 264. It is an odd prime number, the 56th prime in the sequence of primes.

In numeral systems, 263 is represented as 100000111 in binary, 407 in octal, and 0x107 in hexadecimal. In Roman numerals it is CCLXIII.

In mathematics, as a prime, 263 has no positive divisors other than 1 and itself.

In calendar history, the year 263 CE falls within the Crisis of the Third Century of the Roman Empire, a period of military, political, and economic instability.

In telecommunications, the country calling code +263 is assigned to Zimbabwe, so callers dial +263 before local numbers when routing international calls to the country.

In science, ultraviolet wavelengths around 263 nanometers lie in the UV-C range, a part of the spectrum associated with germicidal properties and high-energy radiation.