643566264 has 32 divisors (see below), whose sum is σ = 1755181440. Its totient is φ = 195020000.

The previous prime is 643566221. The next prime is 643566283. The reversal of 643566264 is 462665346.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1218612 + ... + 1219139.

It is an arithmetic number, because the mean of its divisors is an integer number (54849420).

Almost surely, 2^643566264 is an apocalyptic number.

It is an amenable number.

643566264 is an abundant number, since it is smaller than the sum of its proper divisors (1111615176).

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

643566264 is a wasteful number, since it uses less digits than its factorization.

643566264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2437771 (or 2437767 counting only the distinct ones).

The product of its digits is 622080, while the sum is 42.

The square root of 643566264 is about 25368.6078451302. The cubic root of 643566264 is about 863.3715959581.

The spelling of 643566264 in words is "six hundred forty-three million, five hundred sixty-six thousand, two hundred sixty-four".