643022864 has 40 divisors (see below), whose sum is σ = 1374420960. Its totient is φ = 288992000.

The previous prime is 643022851. The next prime is 643022867. The reversal of 643022864 is 468220346.

It is not an unprimeable number, because it can be changed into a prime (643022867) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4862 + ... + 36189.

It is an arithmetic number, because the mean of its divisors is an integer number (34360524).

Almost surely, 2^643022864 is an apocalyptic number.

It is an amenable number.

643022864 is an abundant number, since it is smaller than the sum of its proper divisors (731398096).

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

643022864 is a wasteful number, since it uses less digits than its factorization.

643022864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41159 (or 41153 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 35.

The square root of 643022864 is about 25357.8954962749. The cubic root of 643022864 is about 863.1285294403.

The spelling of 643022864 in words is "six hundred forty-three million, twenty-two thousand, eight hundred sixty-four".