631654640 has 20 divisors (see below), whose sum is σ = 1468597224. Its totient is φ = 252661824.

The previous prime is 631654637. The next prime is 631654697. The reversal of 631654640 is 46456136.

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 631654640.

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, 3947762 + ... + 3947921.

Almost surely, 2^631654640 is an apocalyptic number.

It is an amenable number.

631654640 is an abundant number, since it is smaller than the sum of its proper divisors (836942584).

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

631654640 is a wasteful number, since it uses less digits than its factorization.

631654640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7895696 (or 7895690 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 631654640 is about 25132.7403997256. The cubic root of 631654640 is about 858.0117399770.

The spelling of 631654640 in words is "six hundred thirty-one million, six hundred fifty-four thousand, six hundred forty".