6564255440 has 20 divisors (see below), whose sum is σ = 15261894084. Its totient is φ = 2625702144.

The previous prime is 6564255427. The next prime is 6564255461. The reversal of 6564255440 is 445524656.

It can be written as a sum of positive squares in 2 ways, for example, as 1779489856 + 4784765584 = 42184^2 + 69172^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41026517 + ... + 41026676.

Almost surely, 2^6564255440 is an apocalyptic number.

It is an amenable number.

6564255440 is an abundant number, since it is smaller than the sum of its proper divisors (8697638644).

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

6564255440 is a wasteful number, since it uses less digits than its factorization.

6564255440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82053206 (or 82053200 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 41.

The square root of 6564255440 is about 81020.0928165353. The cubic root of 6564255440 is about 1872.3850186348.

The spelling of 6564255440 in words is "six billion, five hundred sixty-four million, two hundred fifty-five thousand, four hundred forty".