122

122 is a natural number that follows 121 and precedes 123. It is even and composite.

In mathematics, 122 factors as 2 × 61, and both 2 and 61 are prime. Therefore, 122 is a semiprime. Its divisors are 1, 2, 61, and 122, giving it four divisors in total. The sum of its proper divisors (1 + 2 + 61) is 64, so 122 is a deficient number (not perfect or abundant). It is not a square, triangular, or cube.

In various numeral systems, 122 is represented as 1111010 in binary, 172 in octal, and 0x7A or 7A in hexadecimal. In Roman numerals it is written as CXXII.

Beyond pure numbers, 122 appears in historical and cultural contexts. In 122 CE, Roman Emperor Hadrian ordered the construction of Hadrian’s Wall in Britannia. In computing, the decimal value 122 corresponds to the ASCII character 'z'; the Unicode code point U+007A also encodes the same character.