# 270 (number)

(Redirected from 279 (number))
 ← 269 270 271 →
Cardinal two hundred seventy
Ordinal 270th
(two hundred seventieth)
Factorization 2 × 33× 5
Greek numeral ΣΟ´
Roman numeral CCLXX
Binary 1000011102
Ternary 1010003
Quaternary 100324
Quinary 20405
Senary 11306
Octal 4168
Duodecimal 1A612
Vigesimal DA20
Base 36 7I36

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 (sequence A007340 in the OEIS)
• 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
• 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.

## 271–279

### 271

• Two hundred [and] seventy-one prime, twin prime with 269, cuban prime, centered hexagonal number, sum of eleven consecutive primes (7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41 + 43).

### 275

• Two hundred [and] seventy-five 275 = 52·11

### 278

• Two hundred [and] seventy-eight 278 = 2·139, nontotient

### 279

• Two hundred [and] seventy-nine 279 = 32·31 Every positive integer is the sum of at most 279 eighth powers. See Waring's problem

## References

1. ^ "Sloane's A001599 : Harmonic or Ore numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-28.