646040872 has 16 divisors (see below), whose sum is σ = 1220866560. Its totient is φ = 320476464.

The previous prime is 646040819. The next prime is 646040887. The reversal of 646040872 is 278040646.

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, 316918 + ... + 318949.

It is an arithmetic number, because the mean of its divisors is an integer number (76304160).

Almost surely, 2^646040872 is an apocalyptic number.

It is an amenable number.

646040872 is a deficient number, since it is larger than the sum of its proper divisors (574825688).

646040872 is a wasteful number, since it uses less digits than its factorization.

646040872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636000 (or 635996 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 37.

The square root of 646040872 is about 25417.3340852262. The cubic root of 646040872 is about 864.4767780337.

The spelling of 646040872 in words is "six hundred forty-six million, forty thousand, eight hundred seventy-two".