643795568 has 40 divisors (see below), whose sum is σ = 1348174128. Its totient is φ = 296059392.

The previous prime is 643795547. The next prime is 643795573. The reversal of 643795568 is 865597346.

643795568 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 53396 + ... + 64332.

Almost surely, 2^643795568 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643795568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (674087064).

643795568 is an abundant number, since it is smaller than the sum of its proper divisors (704378560).

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

643795568 is a wasteful number, since it uses less digits than its factorization.

643795568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11241 (or 11235 counting only the distinct ones).

The product of its digits is 5443200, while the sum is 53.

The square root of 643795568 is about 25373.1268865310. The cubic root of 643795568 is about 863.4741241479.

The spelling of 643795568 in words is "six hundred forty-three million, seven hundred ninety-five thousand, five hundred sixty-eight".