number.wiki
Number

19

19 is a prime, odd, a calendar year.

Cousin Prime Deficient Number Happy Number Prime Sexy Prime Squarefree Twin Prime Year

Properties

Parity
Odd
Digit count
2
Digit sum
10
Digital root
1
Palindrome
No
Divisor count
2
σ(n) — sum of divisors
20

Primality

19 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 19
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 19)
1 × 19
First multiples
19 · 38 · 57 · 76 · 95 · 114 · 133 · 152 · 171 · 190

Representations

In words
nineteen
Ordinal
19th
Roman numeral
XIX
Binary
10011
Octal
23
Hexadecimal
13

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 17 (gap of 2)
  • Next prime: 23 (gap of 4)

Pair status: twin with 17, cousin with 23.

ASCII character

As an ASCII codepoint, 19 is control character (0x13). ASCII control character.

Hex color
#000013
RGB(0, 0, 19)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.19.