665320311 has 20 divisors (see below), whose sum is σ = 1001476344. Its totient is φ = 440154000.

The previous prime is 665320259. The next prime is 665320319. The reversal of 665320311 is 113023566.

665320311 is a `hidden beast` number, since 6 + 653 + 2 + 0 + 3 + 1 + 1 = 666.

It is not a de Polignac number, because 665320311 - 2⁶ = 665320247 is a prime.

It is a super-2 number, since 2×665320311² = 885302232458273442, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665320319) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 20740 + ... + 41961.

Almost surely, 2^665320311 is an apocalyptic number.

665320311 is a deficient number, since it is larger than the sum of its proper divisors (336156033).

665320311 is a wasteful number, since it uses less digits than its factorization.

665320311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62844 (or 62835 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 665320311 is about 25793.8037326797. The cubic root of 665320311 is about 872.9919934080.

Adding to 665320311 its reverse (113023566), we get a palindrome (778343877).

The spelling of 665320311 in words is "six hundred sixty-five million, three hundred twenty thousand, three hundred eleven".