643712563 has 16 divisors (see below), whose sum is σ = 700068096. Its totient is φ = 588366720.

The previous prime is 643712561. The next prime is 643712567. The reversal of 643712563 is 365217346.

643712563 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 643712563 - 2¹ = 643712561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643712561) 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, 745470 + ... + 746332.

It is an arithmetic number, because the mean of its divisors is an integer number (43754256).

Almost surely, 2^643712563 is an apocalyptic number.

643712563 is a deficient number, since it is larger than the sum of its proper divisors (56355533).

643712563 is a wasteful number, since it uses less digits than its factorization.

643712563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1374.

The product of its digits is 90720, while the sum is 37.

The square root of 643712563 is about 25371.4911465605. The cubic root of 643712563 is about 863.4370131178.

The spelling of 643712563 in words is "six hundred forty-three million, seven hundred twelve thousand, five hundred sixty-three".