6566615511666 has 32 divisors (see below), whose sum is σ = 15010434432000. Its totient is φ = 1876047416976.

The previous prime is 6566615511601. The next prime is 6566615511683. The reversal of 6566615511666 is 6661155166656.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4730166 + ... + 5958833.

It is an arithmetic number, because the mean of its divisors is an integer number (469076076000).

Almost surely, 2^{6566615511666} is an apocalyptic number.

6566615511666 is an abundant number, since it is smaller than the sum of its proper divisors (8443818920334).

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

6566615511666 is a wasteful number, since it uses less digits than its factorization.

6566615511666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10703638.

The product of its digits is 34992000, while the sum is 60.

The spelling of 6566615511666 in words is "six trillion, five hundred sixty-six billion, six hundred fifteen million, five hundred eleven thousand, six hundred sixty-six".