224 (two hundred [and] twenty-four) is the natural number following223 and preceding225.
| ||||
|---|---|---|---|---|
| Cardinal | two hundred twenty-four | |||
| Ordinal | 224th (two hundred twenty-fourth) | |||
| Factorization | 25 × 7 | |||
| Prime | No | |||
| Greek numeral | ΣΚΔ´ | |||
| Roman numeral | CCXXIV,ccxxiv | |||
| Binary | 111000002 | |||
| Ternary | 220223 | |||
| Senary | 10126 | |||
| Octal | 3408 | |||
| Duodecimal | 16812 | |||
| Hexadecimal | E016 | |||
224 is apractical number,[1]and a sum of two positive cubes23 + 63.[2] It is also23 + 33 + 43 + 53, making it one of the smallest numbers to be the sum of distinct positive cubes in more than one way.[3]
224 is the smallestk with λ(k) = 24, where λ(k) is theCarmichael function.[4]
The mathematician and philosopherAlex Bellos suggested in 2014 that a candidate for the lowestuninteresting number would be 224 because it was, at the time, "the lowest number not to have its own page on [the English-language version of]Wikipedia".[5] (As of August 2025, that distinction was held by 317.)
In theSHA-2 family of sixcryptographic hash functions, the weakest is SHA-224, named because it produces 224-bit hash values.[6] It was defined in this way so that the number of bits of security it provides (half of its output length, 112 bits) would match the key length of two-keyTriple DES.[7]
The ancient Phoenicianshekel was a standardized measure ofsilver, equal to 224 grains, although other forms of the shekel employed in other ancient cultures (including the Babylonians and Hebrews) had different measures.[8] Likely not coincidentally, as far as ancientBurma andThailand, silver was measured in a unit called atikal, equal to 224 grains.[9]
