640250317 has 16 divisors (see below), whose sum is σ = 752400000. Its totient is φ = 544558560.

The previous prime is 640250291. The next prime is 640250323. The reversal of 640250317 is 713052046.

640250317 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640250317 - 2⁷ = 640250189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640250357) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37809 + ... + 52057.

It is an arithmetic number, because the mean of its divisors is an integer number (47025000).

Almost surely, 2^640250317 is an apocalyptic number.

It is an amenable number.

640250317 is a deficient number, since it is larger than the sum of its proper divisors (112149683).

640250317 is a wasteful number, since it uses less digits than its factorization.

640250317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14401 (or 14387 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 640250317 is about 25303.1681217985. The cubic root of 640250317 is about 861.8862137907.

The spelling of 640250317 in words is "six hundred forty million, two hundred fifty thousand, three hundred seventeen".