640845000664 has 16 divisors (see below), whose sum is σ = 1310819319720. Its totient is φ = 291293182080.

The previous prime is 640845000619. The next prime is 640845000703. The reversal of 640845000664 is 466000548046.

It is a self number, because there is not a number n which added to its sum of digits gives 640845000664.

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, 3641164689 + ... + 3641164864.

Almost surely, 2^640845000664 is an apocalyptic number.

It is an amenable number.

640845000664 is an abundant number, since it is smaller than the sum of its proper divisors (669974319056).

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

640845000664 is a wasteful number, since it uses less digits than its factorization.

640845000664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7282329570 (or 7282329566 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 43.

The spelling of 640845000664 in words is "six hundred forty billion, eight hundred forty-five million, six hundred sixty-four", and thus it is an aban number.