643564713 has 32 divisors (see below), whose sum is σ = 989683200. Its totient is φ = 367891200.

The previous prime is 643564711. The next prime is 643564739. The reversal of 643564713 is 317465346.

It is not a de Polignac number, because 643564713 - 2¹ = 643564711 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643564711) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 148978 + ... + 153236.

It is an arithmetic number, because the mean of its divisors is an integer number (30927600).

Almost surely, 2^643564713 is an apocalyptic number.

It is an amenable number.

643564713 is a deficient number, since it is larger than the sum of its proper divisors (346118487).

643564713 is a wasteful number, since it uses less digits than its factorization.

643564713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4533.

The product of its digits is 181440, while the sum is 39.

The square root of 643564713 is about 25368.5772758348. The cubic root of 643564713 is about 863.3709023800.

The spelling of 643564713 in words is "six hundred forty-three million, five hundred sixty-four thousand, seven hundred thirteen".