665604956 has 6 divisors (see below), whose sum is σ = 1164808680. Its totient is φ = 332802476.

The previous prime is 665604913. The next prime is 665604959. The reversal of 665604956 is 659406566.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 665604956.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665604959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83200616 + ... + 83200623.

It is an arithmetic number, because the mean of its divisors is an integer number (194134780).

Almost surely, 2^665604956 is an apocalyptic number.

It is an amenable number.

665604956 is a deficient number, since it is larger than the sum of its proper divisors (499203724).

665604956 is a wasteful number, since it uses less digits than its factorization.

665604956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166401243 (or 166401241 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 47.

The square root of 665604956 is about 25799.3208437742. The cubic root of 665604956 is about 873.1164734880.

The spelling of 665604956 in words is "six hundred sixty-five million, six hundred four thousand, nine hundred fifty-six".