664690436 has 12 divisors (see below), whose sum is σ = 1163388828. Its totient is φ = 332293632.

The previous prime is 664690421. The next prime is 664690489. The reversal of 664690436 is 634096466.

It can be written as a sum of positive squares in 2 ways, for example, as 120868036 + 543822400 = 10994^2 + 23320^2 .

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, 43340 + ... + 56636.

It is an arithmetic number, because the mean of its divisors is an integer number (96949069).

Almost surely, 2^664690436 is an apocalyptic number.

It is an amenable number.

664690436 is a deficient number, since it is larger than the sum of its proper divisors (498698392).

664690436 is a wasteful number, since it uses less digits than its factorization.

664690436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25798 (or 25796 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 44.

The square root of 664690436 is about 25781.5910292596. The cubic root of 664690436 is about 872.7164121373.

The spelling of 664690436 in words is "six hundred sixty-four million, six hundred ninety thousand, four hundred thirty-six".