640343654064 has 80 divisors (see below), whose sum is σ = 1882853343840. Its totient is φ = 208241832960.

The previous prime is 640343654047. The next prime is 640343654147. The reversal of 640343654064 is 460456343046.

640343654064 is a `hidden beast` number, since 6 + 4 + 0 + 3 + 43 + 6 + 540 + 64 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18058837 + ... + 18094260.

It is an arithmetic number, because the mean of its divisors is an integer number (23535666798).

Almost surely, 2^640343654064 is an apocalyptic number.

It is an amenable number.

640343654064 is an abundant number, since it is smaller than the sum of its proper divisors (1242509689776).

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

640343654064 is a wasteful number, since it uses less digits than its factorization.

640343654064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36153155 (or 36153143 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 45.

The spelling of 640343654064 in words is "six hundred forty billion, three hundred forty-three million, six hundred fifty-four thousand, sixty-four".