640250694 has 24 divisors (see below), whose sum is σ = 1387879272. Its totient is φ = 213313920.

The previous prime is 640250669. The next prime is 640250707. The reversal of 640250694 is 496052046.

640250694 is a `hidden beast` number, since 64 + 0 + 2 + 506 + 94 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36022 + ... + 50774.

It is an arithmetic number, because the mean of its divisors is an integer number (57828303).

Almost surely, 2^640250694 is an apocalyptic number.

640250694 is an abundant number, since it is smaller than the sum of its proper divisors (747628578).

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

640250694 is a wasteful number, since it uses less digits than its factorization.

640250694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17172 (or 17169 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 640250694 is about 25303.1755714574. The cubic root of 640250694 is about 861.8863829595.

The spelling of 640250694 in words is "six hundred forty million, two hundred fifty thousand, six hundred ninety-four".