number.wiki
Number

80

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

Abundant Number Harshad / Niven Year

Properties

Parity
Even
Digit count
2
Digit sum
8
Digital root
8
Palindrome
No
Divisor count
10
σ(n) — sum of divisors
186

Primality

Prime factorization: 2 4 × 5

Divisors & multiples

All divisors (10)
1 · 2 · 4 · 5 · 8 · 10 · 16 · 20 · 40 · 80
Aliquot sum (sum of proper divisors): 106
Factor pairs (a × b = 80)
1 × 80
2 × 40
4 × 20
5 × 16
8 × 10
First multiples
80 · 160 · 240 · 320 · 400 · 480 · 560 · 640 · 720 · 800

Representations

In words
eighty
Ordinal
80th
Roman numeral
LXXX
Binary
1010000
Octal
120
Hexadecimal
50

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 80, here are decompositions:

  • 7 + 73 = 80
  • 13 + 67 = 80
  • 19 + 61 = 80
  • 37 + 43 = 80
ASCII character

As an ASCII codepoint, 80 is P. Printable ASCII character P.

Network port

TCP/UDP port 80 is the well-known port for HTTP — HyperText Transfer Protocol — the web.

Hex color
#000050
RGB(0, 0, 80)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.80.