6564320644 has 24 divisors (see below), whose sum is σ = 13131937280. Its totient is φ = 2812574016.

The previous prime is 6564320641. The next prime is 6564320657. The reversal of 6564320644 is 4460234656.

It is a junction number, because it is equal to n+sod(n) for n = 6564320597 and 6564320606.

It is not an unprimeable number, because it can be changed into a prime (6564320641) 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, 93037 + ... + 147595.

Almost surely, 2^6564320644 is an apocalyptic number.

It is an amenable number.

6564320644 is an abundant number, since it is smaller than the sum of its proper divisors (6567616636).

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

6564320644 is a wasteful number, since it uses less digits than its factorization.

6564320644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58867 (or 58865 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 40.

The square root of 6564320644 is about 81020.4952095456. The cubic root of 6564320644 is about 1872.3912182000.

The spelling of 6564320644 in words is "six billion, five hundred sixty-four million, three hundred twenty thousand, six hundred forty-four".