number.wiki
Number

21,563

21,563 is a prime, odd.

Cousin Prime Deficient Number Prime Sexy Prime Squarefree

Properties

Parity
Odd
Digit count
5
Digit sum
17
Digital root
8
Palindrome
No
Divisor count
2
σ(n) — sum of divisors
21,564

Primality

21,563 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 21563
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 21,563)
1 × 21563
First multiples
21,563 · 43,126 · 64,689 · 86,252 · 107,815 · 129,378 · 150,941 · 172,504 · 194,067 · 215,630

Representations

In words
twenty-one thousand five hundred sixty-three
Ordinal
21563rd
Binary
101010000111011
Octal
52073
Hexadecimal
543B

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 21,559 (gap of 4)
  • Next prime: 21,569 (gap of 6)

Pair status: cousin with 21559, sexy with 21569.

Unicode codepoint
U+543B
Other letter (Lo)

UTF-8 encoding: E5 90 BB (3 bytes).

Hex color
#00543B
RGB(0, 84, 59)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.84.59.