640792084 has 12 divisors (see below), whose sum is σ = 1187350164. Its totient is φ = 301549184.

The previous prime is 640792069. The next prime is 640792099. The reversal of 640792084 is 480297046.

It is an interprime number because it is at equal distance from previous prime (640792069) and next prime (640792099).

It can be written as a sum of positive squares in 2 ways, for example, as 450627984 + 190164100 = 21228^2 + 13790^2 .

It is a super-2 number, since 2×640792084² = 821228989834126112, 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 in 3 ways as a sum of consecutive naturals, for example, 4711639 + ... + 4711774.

It is an arithmetic number, because the mean of its divisors is an integer number (98945847).

Almost surely, 2^640792084 is an apocalyptic number.

It is an amenable number.

640792084 is a deficient number, since it is larger than the sum of its proper divisors (546558080).

640792084 is a wasteful number, since it uses less digits than its factorization.

640792084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9423434 (or 9423432 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 640792084 is about 25313.8713751966. The cubic root of 640792084 is about 862.1292488727.

The spelling of 640792084 in words is "six hundred forty million, seven hundred ninety-two thousand, eighty-four".