Number
191
191 is a prime, odd, a calendar year.
Properties
- Parity
- Odd
- Digit count
- 3
- Digit sum
- 11
- Digital root
- 2
- Palindrome
- Yes
- Divisor count
- 2
- σ(n) — sum of divisors
- 192
Primality
191 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Aliquot sum (sum of proper divisors):
1
Representations
- In words
- one hundred ninety-one
- Ordinal
- 191st
- Roman numeral
- CXCI
- Binary
- 10111111
- Octal
- 277
- Hexadecimal
- BF
Also seen as
Prime neighborhood
Unicode codepoint
¿
U+00BF
Other punctuation (Po)
UTF-8 encoding: C2 BF (2 bytes).
Hex color
#0000BF
RGB(0, 0, 191)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.191.