640540504 has 16 divisors (see below), whose sum is σ = 1220703120. Its totient is φ = 315019680.

The previous prime is 640540477. The next prime is 640540529. The reversal of 640540504 is 405045046.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 655804 + ... + 656779.

It is an arithmetic number, because the mean of its divisors is an integer number (76293945).

Almost surely, 2^640540504 is an apocalyptic number.

It is an amenable number.

640540504 is a deficient number, since it is larger than the sum of its proper divisors (580162616).

640540504 is a wasteful number, since it uses less digits than its factorization.

640540504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1312650 (or 1312646 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 28.

The square root of 640540504 is about 25308.9016751024. The cubic root of 640540504 is about 862.0164078681.

It can be divided in two parts, 6 and 40540504, that added together give a triangular number (40540510 = T₉₀₀₄).

The spelling of 640540504 in words is "six hundred forty million, five hundred forty thousand, five hundred four".