664211656 has 16 divisors (see below), whose sum is σ = 1245833100. Its totient is φ = 331989504.

The previous prime is 664211629. The next prime is 664211663. The reversal of 664211656 is 656112466.

It can be written as a sum of positive squares in 2 ways, for example, as 663886756 + 324900 = 25766^2 + 570^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12736 + ... + 38608.

Almost surely, 2^664211656 is an apocalyptic number.

It is an amenable number.

664211656 is a deficient number, since it is larger than the sum of its proper divisors (581621444).

664211656 is a wasteful number, since it uses less digits than its factorization.

664211656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29088 (or 29084 counting only the distinct ones).

The product of its digits is 51840, while the sum is 37.

The square root of 664211656 is about 25772.3040491144. The cubic root of 664211656 is about 872.5068210729.

The spelling of 664211656 in words is "six hundred sixty-four million, two hundred eleven thousand, six hundred fifty-six".