Twentytwo

Twentytwo is the natural number that follows twenty-one and precedes twenty-three. It is written as 22 in numerals and as twenty-two in words. The term is formed from the base words twenty and two; its English etymology traces to Old English twentig (twenty) and twa (two), consolidated in Middle English.

In mathematics, 22 is an even and composite number. Its prime factorization is 2 × 11, making it a semiprime. In different numeral systems, 22 appears as XXII in Roman numerals; in binary it is 10110, in octal 26, and in hexadecimal 16.

In science and technology, 22 is the atomic number of titanium, a strong, lightweight metal widely used in aerospace, engineering, and consumer products. In computer networking, the default port for the Secure Shell SSH service is 22.

Culturally, 22 appears in various contexts, including popular media such as the song "22" by Taylor Swift, released in 2012. The number is also a common jersey number in many teams and can signify coming of age or milestone in different cultural settings.

See also: twenty, numerals, and semiprime.