640310664 has 32 divisors (see below), whose sum is σ = 1829459520. Its totient is φ = 182945856.

The previous prime is 640310651. The next prime is 640310669. The reversal of 640310664 is 466013046.

It is not an unprimeable number, because it can be changed into a prime (640310669) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1905519 + ... + 1905854.

It is an arithmetic number, because the mean of its divisors is an integer number (57170610).

Almost surely, 2^640310664 is an apocalyptic number.

It is an amenable number.

640310664 is an abundant number, since it is smaller than the sum of its proper divisors (1189148856).

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

640310664 is a wasteful number, since it uses less digits than its factorization.

640310664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3811389 (or 3811385 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 640310664 is about 25304.3605728341. The cubic root of 640310664 is about 861.9132920610.

The spelling of 640310664 in words is "six hundred forty million, three hundred ten thousand, six hundred sixty-four".