6656660666566 has 16 divisors (see below), whose sum is σ = 10000453201200. Its totient is φ = 3323176581088.

The previous prime is 6656660666531. The next prime is 6656660666567.

6656660666566 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×6656660666566² (a number of 26 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6656660666495 and 6656660666504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6656660666567) 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, 59640420 + ... + 59751928.

It is an arithmetic number, because the mean of its divisors is an integer number (625028325075).

Almost surely, 2^{6656660666566} is an apocalyptic number.

6656660666566 is a deficient number, since it is larger than the sum of its proper divisors (3343792534634).

6656660666566 is a wasteful number, since it uses less digits than its factorization.

6656660666566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157463.

The product of its (nonzero) digits is 1511654400, while the sum is 70.

The spelling of 6656660666566 in words is "six trillion, six hundred fifty-six billion, six hundred sixty million, six hundred sixty-six thousand, five hundred sixty-six".