6665555666 has 32 divisors (see below), whose sum is σ = 12492627840. Its totient is φ = 2591308800.

The previous prime is 6665555657. The next prime is 6665555681.

6665555666 is nontrivially palindromic in base 10.

It is a Curzon number.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24050 + ... + 117938.

It is an arithmetic number, because the mean of its divisors is an integer number (390394620).

Almost surely, 2^6665555666 is an apocalyptic number.

6665555666 is a deficient number, since it is larger than the sum of its proper divisors (5827072174).

6665555666 is a wasteful number, since it uses less digits than its factorization.

6665555666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94370.

The product of its digits is 29160000, while the sum is 56.

The square root of 6665555666 is about 81642.8543474565. The cubic root of 6665555666 is about 1881.9675027883.

The spelling of 6665555666 in words is "six billion, six hundred sixty-five million, five hundred fifty-five thousand, six hundred sixty-six".