640204402664 has 16 divisors (see below), whose sum is σ = 1218299424000. Its totient is φ = 315324556272.

The previous prime is 640204402639. The next prime is 640204402751. The reversal of 640204402664 is 466204402046.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 597205064 + ... + 597206135.

It is an arithmetic number, because the mean of its divisors is an integer number (76143714000).

Almost surely, 2^640204402664 is an apocalyptic number.

It is an amenable number.

640204402664 is a deficient number, since it is larger than the sum of its proper divisors (578095021336).

640204402664 is a wasteful number, since it uses less digits than its factorization.

640204402664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1194411272 (or 1194411268 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 38.

The spelling of 640204402664 in words is "six hundred forty billion, two hundred four million, four hundred two thousand, six hundred sixty-four".