Number
684
684 is a composite number, even, a calendar year.
Properties
- Parity
- Even
- Digit count
- 3
- Digit sum
- 18
- Digital root
- 9
- Palindrome
- No
- Divisor count
- 18
- σ(n) — sum of divisors
- 1,820
Primality
Prime factorization: 2 2 × 3 2 × 19
Divisors & multiples
All divisors (18)
Aliquot sum (sum of proper divisors):
1,136
Representations
- In words
- six hundred eighty-four
- Ordinal
- 684th
- Roman numeral
- DCLXXXIV
- Binary
- 1010101100
- Octal
- 1254
- Hexadecimal
- 2AC
Also seen as
Goldbach decomposition
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 684, here are decompositions:
- 7 + 677 = 684
- 11 + 673 = 684
- 23 + 661 = 684
- 31 + 653 = 684
- 37 + 647 = 684
- 41 + 643 = 684
- 43 + 641 = 684
- 53 + 631 = 684
Showing the first eight; more decompositions exist.
Unicode codepoint
ʬ
U+02AC
Lowercase letter (Ll)
UTF-8 encoding: CA AC (2 bytes).
Hex color
#0002AC
RGB(0, 2, 172)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.2.172.