Number
1,688
1,688 is a composite number, even, a calendar year.
Properties
- Parity
- Even
- Digit count
- 4
- Digit sum
- 23
- Digital root
- 5
- Palindrome
- No
- Divisor count
- 8
- σ(n) — sum of divisors
- 3,180
Primality
Prime factorization: 2 3 × 211
Divisors & multiples
Aliquot sum (sum of proper divisors):
1,492
First multiples
Representations
- In words
- one thousand six hundred eighty-eight
- Ordinal
- 1688th
- Roman numeral
- MDCLXXXVIII
- Binary
- 11010011000
- Octal
- 3230
- Hexadecimal
- 698
Also seen as
Goldbach decomposition
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1688, here are decompositions:
- 19 + 1669 = 1688
- 31 + 1657 = 1688
- 61 + 1627 = 1688
- 67 + 1621 = 1688
- 79 + 1609 = 1688
- 109 + 1579 = 1688
- 139 + 1549 = 1688
- 157 + 1531 = 1688
Showing the first eight; more decompositions exist.
Unicode codepoint
ژ
U+0698
Other letter (Lo)
UTF-8 encoding: DA 98 (2 bytes).
Hex color
#000698
RGB(0, 6, 152)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.152.