278 (two hundred [and] seventy-eight) is the natural number following 277 and preceding 279.
| ||||
|---|---|---|---|---|
| Cardinal | two hundred seventy-eight | |||
| Ordinal | 278th (two hundred seventy-eighth) | |||
| Factorization | 2 × 139 | |||
| Divisors | 1, 2, 139, 278 | |||
| Greek numeral | ΣΟΗ´ | |||
| Roman numeral | CCLXXVIII, cclxxviii | |||
| Binary | 1000101102 | |||
| Ternary | 1010223 | |||
| Senary | 11426 | |||
| Octal | 4268 | |||
| Duodecimal | 1B212 | |||
| Hexadecimal | 11616 | |||
In mathematics
edit- 278 is an even composite number with 2 prime factors.[1]
- 278 is equal to Φ(30). It is the sum of the totient function.[2]
- 278 is a nontotient number which means that it is an even number that doesn't follow Euler's totient function.[3]
- 278 is the smallest semiprime number that has an anagram that is also semiprime. The other number is 287.[4]
References
edit- ^ "Composite numbers". mathworld.wolfram.com.
- ^ Sloane, N. J. A. (ed.). "Sequence A002088". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
- ^ "Nontotient numbers". mathworld.wolfram.com.
- ^ "Semiprime numbers". mathworld.wolfram.com.