6666006665 has 8 divisors (see below), whose sum is σ = 8000711880. Its totient is φ = 5331802752.

The previous prime is 6666006647. The next prime is 6666006701. The reversal of 6666006665 is 5666006666.

It can be written as a sum of positive squares in 4 ways, for example, as 704159296 + 5961847369 = 26536^2 + 77213^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6666006665 - 2²² = 6661812361 is a prime.

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, 95420 + ... + 149789.

It is an arithmetic number, because the mean of its divisors is an integer number (1000088985).

Almost surely, 2^6666006665 is an apocalyptic number.

It is an amenable number.

6666006665 is a deficient number, since it is larger than the sum of its proper divisors (1334705215).

6666006665 is a wasteful number, since it uses less digits than its factorization.

6666006665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250651.

The product of its (nonzero) digits is 1399680, while the sum is 47.

The square root of 6666006665 is about 81645.6163244543. The cubic root of 6666006665 is about 1882.0099471776.

Subtracting from 6666006665 its reverse (5666006666), we obtain a palindrome (999999999).

The spelling of 6666006665 in words is "six billion, six hundred sixty-six million, six thousand, six hundred sixty-five".