640256926 has 8 divisors (see below), whose sum is σ = 961572024. Its totient is φ = 319732920.

The previous prime is 640256921. The next prime is 640256959. The reversal of 640256926 is 629652046.

640256926 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640256921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 195745 + ... + 198988.

It is an arithmetic number, because the mean of its divisors is an integer number (120196503).

Almost surely, 2^640256926 is an apocalyptic number.

640256926 is a deficient number, since it is larger than the sum of its proper divisors (321315098).

640256926 is a wasteful number, since it uses less digits than its factorization.

640256926 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395546.

The product of its (nonzero) digits is 155520, while the sum is 40.

The square root of 640256926 is about 25303.2987177561. The cubic root of 640256926 is about 861.8891793946.

The spelling of 640256926 in words is "six hundred forty million, two hundred fifty-six thousand, nine hundred twenty-six".