668565908 has 12 divisors (see below), whose sum is σ = 1170176532. Its totient is φ = 334229760.

The previous prime is 668565889. The next prime is 668565923. The reversal of 668565908 is 809565866.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 280160644 + 388405264 = 16738^2 + 19708^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 668565908.

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, 32516 + ... + 48932.

It is an arithmetic number, because the mean of its divisors is an integer number (97514711).

Almost surely, 2^668565908 is an apocalyptic number.

It is an amenable number.

668565908 is a deficient number, since it is larger than the sum of its proper divisors (501610624).

668565908 is a wasteful number, since it uses less digits than its factorization.

668565908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26602 (or 26600 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 53.

The square root of 668565908 is about 25856.6414679092. The cubic root of 668565908 is about 874.4092482672.

The spelling of 668565908 in words is "six hundred sixty-eight million, five hundred sixty-five thousand, nine hundred eight".