6561288864 has 72 divisors (see below), whose sum is σ = 20093958612. Its totient is φ = 2018856960.

The previous prime is 6561288857. The next prime is 6561288869. The reversal of 6561288864 is 4688821656.

It can be written as a sum of positive squares in 2 ways, for example, as 6194949264 + 366339600 = 78708^2 + 19140^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a self number, because there is not a number n which added to its sum of digits gives 6561288864.

It is not an unprimeable number, because it can be changed into a prime (6561288869) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 872497 + ... + 879984.

Almost surely, 2^6561288864 is an apocalyptic number.

It is an amenable number.

6561288864 is an abundant number, since it is smaller than the sum of its proper divisors (13532669748).

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

6561288864 is a wasteful number, since it uses less digits than its factorization.

6561288864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1752510 (or 1752499 counting only the distinct ones).

The product of its digits is 4423680, while the sum is 54.

The square root of 6561288864 is about 81001.7830914851. The cubic root of 6561288864 is about 1872.1029145700.

The spelling of 6561288864 in words is "six billion, five hundred sixty-one million, two hundred eighty-eight thousand, eight hundred sixty-four".