640053656 has 16 divisors (see below), whose sum is σ = 1309200840. Its totient is φ = 290933440.

The previous prime is 640053649. The next prime is 640053671. The reversal of 640053656 is 656350046.

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, 3636581 + ... + 3636756.

Almost surely, 2^640053656 is an apocalyptic number.

It is an amenable number.

640053656 is an abundant number, since it is smaller than the sum of its proper divisors (669147184).

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

640053656 is a wasteful number, since it uses less digits than its factorization.

640053656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7273354 (or 7273350 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 35.

The square root of 640053656 is about 25299.2817289345. The cubic root of 640053656 is about 861.7979583289.

The spelling of 640053656 in words is "six hundred forty million, fifty-three thousand, six hundred fifty-six".