6566755566 has 32 divisors (see below), whose sum is σ = 15799714560. Its totient is φ = 1777467456.

The previous prime is 6566755537. The next prime is 6566755577. The reversal of 6566755566 is 6655576656.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4113711 + ... + 4115306.

It is an arithmetic number, because the mean of its divisors is an integer number (493741080).

Almost surely, 2^6566755566 is an apocalyptic number.

6566755566 is an abundant number, since it is smaller than the sum of its proper divisors (9232958994).

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

6566755566 is a wasteful number, since it uses less digits than its factorization.

6566755566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8229048.

The product of its digits is 34020000, while the sum is 57.

The square root of 6566755566 is about 81035.5203969222. The cubic root of 6566755566 is about 1872.6227000356.

The spelling of 6566755566 in words is "six billion, five hundred sixty-six million, seven hundred fifty-five thousand, five hundred sixty-six".