Number
428
428 is a composite number, even, a calendar year.
Properties
- Parity
- Even
- Digit count
- 3
- Digit sum
- 14
- Digital root
- 5
- Palindrome
- No
- Divisor count
- 6
- σ(n) — sum of divisors
- 756
Primality
Prime factorization: 2 2 × 107
Divisors & multiples
Aliquot sum (sum of proper divisors):
328
Representations
- In words
- four hundred twenty-eight
- Ordinal
- 428th
- Roman numeral
- CDXXVIII
- Binary
- 110101100
- Octal
- 654
- Hexadecimal
- 1AC
Also seen as
Goldbach decomposition
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 428, here are decompositions:
- 7 + 421 = 428
- 19 + 409 = 428
- 31 + 397 = 428
- 61 + 367 = 428
- 79 + 349 = 428
- 97 + 331 = 428
- 151 + 277 = 428
- 157 + 271 = 428
Showing the first eight; more decompositions exist.
Unicode codepoint
Ƭ
U+01AC
Uppercase letter (Lu)
UTF-8 encoding: C6 AC (2 bytes).
Hex color
#0001AC
RGB(0, 1, 172)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.172.