# 270 (number)

Short description: Natural number
 ← 269 270 271 →
Cardinaltwo hundred seventy
Ordinal270th
(two hundred seventieth)
Factorization2 × 33 × 5
Greek numeralΣΟ´
Roman numeralCCLXX
Binary1000011102
Ternary1010003
Quaternary100324
Quinary20405
Senary11306
Octal4168
Duodecimal1A612
Hexadecimal10E16
VigesimalDA20
Base 367I36

270 (two hundred [and] seventy) is the natural number following 269 and preceding 271.

## In mathematics

• 270 is a harmonic divisor number[1]
• 270 is the fourth number that is divisible by its average integer divisor[2]
• 270 is a practical number, by the second definition
• The sum of the coprime counts for the first 29 integers is 270
• 270 is a sparsely totient number, the largest integer with 72 as its totient
• Given 6 elements, there are 270 square permutations[3]
• 10! has 270 divisors
• 270 is a Harshad number in base 10
• 270 is the smallest positive integer that has divisors ending by digits 1, 2, ..., 9.
• 270 is the smallest sum of a set of even numbers that contain every digit once.

## In other fields

• The year 270 BC
• The year 270 AD
• The caliber of the .270 Winchester rifle
• The number of U.S. Electoral College votes needed to be elected President of the United States
• The average number of days in human pregnancy

## Integers from 271 to 279

### 271

Main page: 271 (number)

### 272

272 = 24·17, sum of four consecutive primes (61 + 67 + 71 + 73), Euler number, primitive semiperfect number, pronic number. 272 is the smallest palindrome divisible by a fourth power.

### 273

Main page: 273 (number)

### 274

274 = 2·137, tribonacci number, Smith number, nontotient, noncototient, centered triangular number, 27464 + 1 is prime

### 275

275 = 52·11. 275 is the sum of fifth powers of the first two primes. The maximal number of pieces that can be obtained by cutting an annulus with 22 cuts.[4]

### 276

Main page: 276 (number)

### 277

Main page: 277 (number)

### 278

278 = 2·139 = Φ(30),[5] nontotient. 278 is the smallest semiprime such that the next semiprime (287) is its anagram.

### 279

279 = 32·31. Every positive integer is the sum of at most 279 eighth powers. See Waring's problem.

## References

1. Sloane, N. J. A., ed. "Sequence A001599 (Harmonic or Ore numbers)". OEIS Foundation. Retrieved 2016-05-28.
2. Sloane, N. J. A., ed. "Sequence A007340". OEIS Foundation.
3. Sloane, N. J. A., ed. "Sequence A003483". OEIS Foundation.
4. Sloane, N. J. A., ed. "Sequence A000096". OEIS Foundation.
5. Sloane, N. J. A., ed. "Sequence A002088". OEIS Foundation.