Number
15
15 is a composite number, odd, a calendar year.
Properties
- Parity
- Odd
- Digit count
- 2
- Digit sum
- 6
- Digital root
- 6
- Palindrome
- No
- Divisor count
- 4
- σ(n) — sum of divisors
- 24
Primality
Prime factorization: 3 × 5
Divisors & multiples
Aliquot sum (sum of proper divisors):
9
Representations
- In words
- fifteen
- Ordinal
- 15th
- Roman numeral
- XV
- Binary
- 1111
- Octal
- 17
- Hexadecimal
- F
Also seen as
ASCII character
As an ASCII codepoint, 15 is control character (0x0F). ASCII control character.
Hex color
#00000F
RGB(0, 0, 15)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.15.