643071368 has 16 divisors (see below), whose sum is σ = 1212009180. Its totient is φ = 319868928.

The previous prime is 643071367. The next prime is 643071383. The reversal of 643071368 is 863170346.

It can be written as a sum of positive squares in 2 ways, for example, as 590392804 + 52678564 = 24298^2 + 7258^2 .

It is not an unprimeable number, because it can be changed into a prime (643071367) 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, 206705 + ... + 209792.

Almost surely, 2^643071368 is an apocalyptic number.

It is an amenable number.

643071368 is a deficient number, since it is larger than the sum of its proper divisors (568937812).

643071368 is a wasteful number, since it uses less digits than its factorization.

643071368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416696 (or 416692 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 38.

The square root of 643071368 is about 25358.8518667545. The cubic root of 643071368 is about 863.1502311743.

The spelling of 643071368 in words is "six hundred forty-three million, seventy-one thousand, three hundred sixty-eight".