number.wiki
Number

22

22 is a composite number, even, a calendar year.

Deficient Number Palindrome Pentagonal Repdigit Smith Number Squarefree Year

Properties

Parity
Even
Digit count
2
Digit sum
4
Digital root
4
Palindrome
Yes
Divisor count
4
σ(n) — sum of divisors
36

Primality

Prime factorization: 2 × 11

Divisors & multiples

All divisors (4)
1 · 2 · 11 · 22
Aliquot sum (sum of proper divisors): 14
Factor pairs (a × b = 22)
1 × 22
2 × 11
First multiples
22 · 44 · 66 · 88 · 110 · 132 · 154 · 176 · 198 · 220

Representations

In words
twenty-two
Ordinal
22nd
Roman numeral
XXII
Binary
10110
Octal
26
Hexadecimal
16

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 22, here are decompositions:

  • 3 + 19 = 22
  • 5 + 17 = 22
  • 11 + 11 = 22
ASCII character

As an ASCII codepoint, 22 is control character (0x16). ASCII control character.

Network port

TCP/UDP port 22 is the well-known port for SSH — Secure Shell — encrypted remote login.

Hex color
#000016
RGB(0, 0, 22)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.22.