Number
678
678 is a composite number, even, a calendar year.
Properties
- Parity
- Even
- Digit count
- 3
- Digit sum
- 21
- Digital root
- 3
- Palindrome
- No
- Divisor count
- 8
- σ(n) — sum of divisors
- 1,368
Primality
Prime factorization: 2 × 3 × 113
Divisors & multiples
Aliquot sum (sum of proper divisors):
690
Representations
- In words
- six hundred seventy-eight
- Ordinal
- 678th
- Roman numeral
- DCLXXVIII
- Binary
- 1010100110
- Octal
- 1246
- Hexadecimal
- 2A6
Also seen as
Goldbach decomposition
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 678, here are decompositions:
- 5 + 673 = 678
- 17 + 661 = 678
- 19 + 659 = 678
- 31 + 647 = 678
- 37 + 641 = 678
- 47 + 631 = 678
- 59 + 619 = 678
- 61 + 617 = 678
Showing the first eight; more decompositions exist.
Unicode codepoint
ʦ
U+02A6
Lowercase letter (Ll)
UTF-8 encoding: CA A6 (2 bytes).
Hex color
#0002A6
RGB(0, 2, 166)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.2.166.