640600645040 has 40 divisors (see below), whose sum is σ = 1490461375200. Its totient is φ = 256057053696.

The previous prime is 640600645031. The next prime is 640600645067. The reversal of 640600645040 is 40546006046.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2749949 + ... + 2973788.

It is an arithmetic number, because the mean of its divisors is an integer number (37261534380).

Almost surely, 2^640600645040 is an apocalyptic number.

It is an amenable number.

640600645040 is an abundant number, since it is smaller than the sum of its proper divisors (849860730160).

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

640600645040 is a wasteful number, since it uses less digits than its factorization.

640600645040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5725149 (or 5725143 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

The spelling of 640600645040 in words is "six hundred forty billion, six hundred million, six hundred forty-five thousand, forty".