number.wiki
Number

84

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

Abundant Number Harshad / Niven Tetrahedral Year

Properties

Parity
Even
Digit count
2
Digit sum
12
Digital root
3
Palindrome
No
Divisor count
12
σ(n) — sum of divisors
224

Primality

Prime factorization: 2 2 × 3 × 7

Divisors & multiples

All divisors (12)
1 · 2 · 3 · 4 · 6 · 7 · 12 · 14 · 21 · 28 · 42 · 84
Aliquot sum (sum of proper divisors): 140
Factor pairs (a × b = 84)
1 × 84
2 × 42
3 × 28
4 × 21
6 × 14
7 × 12
First multiples
84 · 168 · 252 · 336 · 420 · 504 · 588 · 672 · 756 · 840

Representations

In words
eighty-four
Ordinal
84th
Roman numeral
LXXXIV
Binary
1010100
Octal
124
Hexadecimal
54

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 84, here are decompositions:

  • 5 + 79 = 84
  • 11 + 73 = 84
  • 13 + 71 = 84
  • 17 + 67 = 84
  • 23 + 61 = 84
  • 31 + 53 = 84
  • 37 + 47 = 84
  • 41 + 43 = 84

Showing the first eight; more decompositions exist.

ASCII character

As an ASCII codepoint, 84 is T. Printable ASCII character T.

Hex color
#000054
RGB(0, 0, 84)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.84.

Possible US bank routing number

This passes the ABA routing number checksum and matches the Federal Reserve numbering scheme.

Routing number
000000084
Federal Reserve
United States Government

Banks operate many routing numbers per state and division; an unmatched checksum-valid number can still be a real RTN at a smaller institution.