number.wiki
Number

842

842 is a composite number, even, a calendar year.

Deficient Number Squarefree Year

Properties

Parity
Even
Digit count
3
Digit sum
14
Digital root
5
Palindrome
No
Divisor count
4
σ(n) — sum of divisors
1,266

Primality

Prime factorization: 2 × 421

Divisors & multiples

All divisors (4)
1 · 2 · 421 · 842
Aliquot sum (sum of proper divisors): 424
Factor pairs (a × b = 842)
1 × 842
2 × 421
First multiples
842 · 1,684 · 2,526 · 3,368 · 4,210 · 5,052 · 5,894 · 6,736 · 7,578 · 8,420

Representations

In words
eight hundred forty-two
Ordinal
842nd
Roman numeral
DCCCXLII
Binary
1101001010
Octal
1512
Hexadecimal
34A

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 842, here are decompositions:

  • 3 + 839 = 842
  • 13 + 829 = 842
  • 19 + 823 = 842
  • 31 + 811 = 842
  • 73 + 769 = 842
  • 103 + 739 = 842
  • 109 + 733 = 842
  • 151 + 691 = 842

Showing the first eight; more decompositions exist.

Unicode codepoint
͊
U+034A
Non-spacing mark (Mn)

UTF-8 encoding: CD 8A (2 bytes).

Hex color
#00034A
RGB(0, 3, 74)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.3.74.