6666665 has 16 divisors (see below), whose sum is σ = 8640000. Its totient is φ = 4923072.

The previous prime is 6666617. The next prime is 6666679. The reversal of 6666665 is 5666666.

It is a cyclic number.

It is not a de Polignac number, because 6666665 - 2¹⁶ = 6601129 is a prime.

It is a nialpdrome in base 10.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2336 + ... + 4334.

It is an arithmetic number, because the mean of its divisors is an integer number (540000).

Almost surely, 2^6666665 is an apocalyptic number.

It is an amenable number.

6666665 is a deficient number, since it is larger than the sum of its proper divisors (1973335).

6666665 is a wasteful number, since it uses less digits than its factorization.

6666665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2056.

The product of its digits is 233280, while the sum is 41.

The square root of 6666665 is about 2581.9885747230. The cubic root of 6666665 is about 188.2071900923.

Subtracting from 6666665 its reverse (5666666), we obtain a palindrome (999999).

The spelling of 6666665 in words is "six million, six hundred sixty-six thousand, six hundred sixty-five".