52 (number)
Natural number
From Wikipedia, the free encyclopedia
52 (fifty-two) is the natural number following 51 and preceding 53.
| ||||
|---|---|---|---|---|
| Cardinal | fifty-two | |||
| Ordinal | 52nd (fifty-second) | |||
| Factorization | 22 × 13 | |||
| Divisors | 1, 2, 4, 13, 26, 52 | |||
| Greek numeral | ΝΒ´ | |||
| Roman numeral | LII, lii | |||
| Binary | 1101002 | |||
| Ternary | 12213 | |||
| Senary | 1246 | |||
| Octal | 648 | |||
| Duodecimal | 4412 | |||
| Hexadecimal | 3416 | |||
In mathematics
Fifty-two is
- a composite number; a square-prime, of the form p2 · q , where q is some prime larger than p . It is the sixth of this form and the fifth of the form 22 · q .
- the 5th Bell number,[1] the number of ways to partition a set of 5 objects.
- a decagonal number.[2]
- with an aliquot sum of 46; within an aliquot sequence of seven composite numbers { 52, 46, 26, 16, 15, 9, 4, 3, 1, 0 } to the prime in the 3-aliquot tree. This sequence does not extend above 52 because it is,
- an untouchable number, since it is never the sum of proper divisors of any number. It is the first untouchable number larger than 2 and 5.[3]
- a noncototient since it is not equal to x − φ(x) for any x .[4]
- a vertically symmetrical number, (as on calculator displays).[5]
In other fields
Fifty-two is:
- The number of cards in a standard deck of playing cards, not counting Jokers or advertisement cards
- The number of weeks in a calendar year
- The number of white keys on a piano