Number
138
138 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
- 288
Primality
Prime factorization: 2 × 3 × 23
Divisors & multiples
Aliquot sum (sum of proper divisors):
150
Representations
- In words
- one hundred thirty-eight
- Ordinal
- 138th
- Roman numeral
- CXXXVIII
- Binary
- 10001010
- Octal
- 212
- Hexadecimal
- 8A
Also seen as
Goldbach decomposition
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 138, here are decompositions:
- 7 + 131 = 138
- 11 + 127 = 138
- 29 + 109 = 138
- 31 + 107 = 138
- 37 + 101 = 138
- 41 + 97 = 138
- 59 + 79 = 138
- 67 + 71 = 138
Showing the first eight; more decompositions exist.
Unicode codepoint
U+008A
Control character (Cc)
UTF-8 encoding: C2 8A (2 bytes).
Hex color
#00008A
RGB(0, 0, 138)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.138.