Number
642
642 is a composite number, even, a calendar year.
Properties
- Parity
- Even
- Digit count
- 3
- Digit sum
- 12
- Digital root
- 3
- Palindrome
- No
- Divisor count
- 8
- σ(n) — sum of divisors
- 1,296
Primality
Prime factorization: 2 × 3 × 107
Divisors & multiples
Aliquot sum (sum of proper divisors):
654
Representations
- In words
- six hundred forty-two
- Ordinal
- 642nd
- Roman numeral
- DCXLII
- Binary
- 1010000010
- Octal
- 1202
- Hexadecimal
- 282
Also seen as
Goldbach decomposition
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 642, here are decompositions:
- 11 + 631 = 642
- 23 + 619 = 642
- 29 + 613 = 642
- 41 + 601 = 642
- 43 + 599 = 642
- 71 + 571 = 642
- 73 + 569 = 642
- 79 + 563 = 642
Showing the first eight; more decompositions exist.
Unicode codepoint
ʂ
U+0282
Lowercase letter (Ll)
UTF-8 encoding: CA 82 (2 bytes).
Hex color
#000282
RGB(0, 2, 130)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.2.130.