643386344 has 32 divisors (see below), whose sum is σ = 1254501000. Its totient is φ = 308969472.

The previous prime is 643386329. The next prime is 643386389. The reversal of 643386344 is 443683346.

643386344 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 514836100 + 128550244 = 22690^2 + 11338^2 .

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, 37592 + ... + 51960.

Almost surely, 2^643386344 is an apocalyptic number.

It is an amenable number.

643386344 is a deficient number, since it is larger than the sum of its proper divisors (611114656).

643386344 is a wasteful number, since it uses less digits than its factorization.

643386344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14597 (or 14593 counting only the distinct ones).

The product of its digits is 497664, while the sum is 41.

The square root of 643386344 is about 25365.0614822831. The cubic root of 643386344 is about 863.2911316743.

The spelling of 643386344 in words is "six hundred forty-three million, three hundred eighty-six thousand, three hundred forty-four".