Number
91
91 is a composite number, odd, a calendar year.
Properties
- Parity
- Odd
- Digit count
- 2
- Digit sum
- 10
- Digital root
- 1
- Palindrome
- No
- Divisor count
- 4
- σ(n) — sum of divisors
- 112
Primality
Prime factorization: 7 × 13
Divisors & multiples
Aliquot sum (sum of proper divisors):
21
Representations
- In words
- ninety-one
- Ordinal
- 91st
- Roman numeral
- XCI
- Binary
- 1011011
- Octal
- 133
- Hexadecimal
- 5B
Also seen as
ASCII character
As an ASCII codepoint, 91 is [. Printable ASCII character [.
Hex color
#00005B
RGB(0, 0, 91)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.91.