665266128 has 20 divisors (see below), whose sum is σ = 1718604288. Its totient is φ = 221755360.

The previous prime is 665266079. The next prime is 665266139. The reversal of 665266128 is 821662566.

It is a super-2 number, since 2×665266128² = 885158042128224768, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 665266128.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6929808 + ... + 6929903.

Almost surely, 2^665266128 is an apocalyptic number.

It is an amenable number.

665266128 is an abundant number, since it is smaller than the sum of its proper divisors (1053338160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665266128 is a wasteful number, since it uses less digits than its factorization.

665266128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13859722 (or 13859716 counting only the distinct ones).

The product of its digits is 207360, while the sum is 42.

The square root of 665266128 is about 25792.7534009070. The cubic root of 665266128 is about 872.9682942421.

The spelling of 665266128 in words is "six hundred sixty-five million, two hundred sixty-six thousand, one hundred twenty-eight".