Twenty two

The twenty-two (22) is the natural number that follows twenty-one and precedes twenty-three.

Math

• 22 is a composite number, which has the following factors: 1, 2 and 11. As the sum of its factors is 14 ≤ 22, it is a defective number. The sum of its dividers 1, 2, 11 and 22 = 36.
• Number two.
• Redigit number.
• Casualty number.
• Pentagonal number.
• Based 10, 2nd Smith's number.
• A Perrin number.
• 2.o number de Erdős-Woods.
• 8th semi-primary number.
• 22 divided between 7 approaches the irrational number π.
• Free number of squares.
• Størmer number.
• 22 is the number of partitions of 8.
• 22! (factory of 22) has 22 digits.

Other sciences

Chemistry

• It's the atomic number of titanium.

Astronomy

• Messier M22 is a globular cluster in the constellation of Sagittarius.
• Object of the New General Catalog NGC 22 is a spiral galaxy located in the Pegasus constellation.
• 22P/Kopff is a periodic comet of the Solar System.
• 22) Kalliope is an asteroid that forms part of the asteroid belt.

Technology

• The Bell-Boeing V-22 Osprey is a multipurpose military aircraft.
• Lockheed Martin F-22 Raptor is a fifth-generation hunting plane.