Number
561
561 is a composite number, odd, a calendar year.
Properties
- Parity
- Odd
- Digit count
- 3
- Digit sum
- 12
- Digital root
- 3
- Palindrome
- No
- Divisor count
- 8
- σ(n) — sum of divisors
- 864
Primality
Prime factorization: 3 × 11 × 17
Divisors & multiples
Aliquot sum (sum of proper divisors):
303
Representations
- In words
- five hundred sixty-one
- Ordinal
- 561st
- Roman numeral
- DLXI
- Binary
- 1000110001
- Octal
- 1061
- Hexadecimal
- 231
Also seen as
Unicode codepoint
ȱ
U+0231
Lowercase letter (Ll)
UTF-8 encoding: C8 B1 (2 bytes).
Hex color
#000231
RGB(0, 2, 49)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.2.49.