640382172 has 24 divisors (see below), whose sum is σ = 1495111296. Its totient is φ = 213334128.

The previous prime is 640382153. The next prime is 640382189. The reversal of 640382172 is 271283046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6513 + ... + 36375.

It is an arithmetic number, because the mean of its divisors is an integer number (62296304).

Almost surely, 2^640382172 is an apocalyptic number.

It is an amenable number.

640382172 is an abundant number, since it is smaller than the sum of its proper divisors (854729124).

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

640382172 is a wasteful number, since it uses less digits than its factorization.

640382172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31657 (or 31655 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 640382172 is about 25305.7734914387. The cubic root of 640382172 is about 861.9453761752.

The spelling of 640382172 in words is "six hundred forty million, three hundred eighty-two thousand, one hundred seventy-two".