665279 has 2 divisors, whose sum is σ = 665280. Its totient is φ = 665278.

The previous prime is 665267. The next prime is 665293. The reversal of 665279 is 972566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665279 - 2¹² = 661183 is a prime.

It is a super-2 number, since 2×665279² = 885192295682, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a d-powerful number, because it can be written as 6⁴ + 6⁴ + 2¹⁷ + 5³ + 7² + 9⁶ .

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332639 + 332640.

It is an arithmetic number, because the mean of its divisors is an integer number (332640).

2⁶⁶⁵²⁷⁹ is an apocalyptic number.

665279 is a deficient number, since it is larger than the sum of its proper divisors (1).

665279 is an equidigital number, since it uses as much as digits as its factorization.

665279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 35.

The square root of 665279 is about 815.6463694519. The cubic root of 665279 is about 87.2973924458.

The spelling of 665279 in words is "six hundred sixty-five thousand, two hundred seventy-nine".