66665656666 has 16 divisors (see below), whose sum is σ = 117071398080. Its totient is φ = 27874141920.

The previous prime is 66665656657. The next prime is 66665656697.

66665656666 is nontrivially palindromic in base 10.

66665656666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 66665656598 and 66665656607.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58070556 + ... + 58071703.

It is an arithmetic number, because the mean of its divisors is an integer number (7316962380).

Almost surely, 2^66665656666 is an apocalyptic number.

66665656666 is a deficient number, since it is larger than the sum of its proper divisors (50405741414).

66665656666 is a wasteful number, since it uses less digits than its factorization.

66665656666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116142309.

The product of its digits is 251942400, while the sum is 64.

The spelling of 66665656666 in words is "sixty-six billion, six hundred sixty-five million, six hundred fifty-six thousand, six hundred sixty-six".