640885204 has 6 divisors (see below), whose sum is σ = 1121549114. Its totient is φ = 320442600.

The previous prime is 640885183. The next prime is 640885211. The reversal of 640885204 is 402588046.

It can be written as a sum of positive squares in only one way, i.e., 595457604 + 45427600 = 24402^2 + 6740^2 .

It is a super-2 number, since 2×640885204² = 821467689412243232, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80110647 + ... + 80110654.

Almost surely, 2^640885204 is an apocalyptic number.

It is an amenable number.

640885204 is a deficient number, since it is larger than the sum of its proper divisors (480663910).

640885204 is a wasteful number, since it uses less digits than its factorization.

640885204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160221305 (or 160221303 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 37.

The square root of 640885204 is about 25315.7106161372. The cubic root of 640885204 is about 862.1710084330.

The spelling of 640885204 in words is "six hundred forty million, eight hundred eighty-five thousand, two hundred four".