6666665215 has 16 divisors (see below), whose sum is σ = 9231625728. Its totient is φ = 4527042336.

The previous prime is 6666665197. The next prime is 6666665219. The reversal of 6666665215 is 5125666666.

It is a cyclic number.

It is not a de Polignac number, because 6666665215 - 2¹¹ = 6666663167 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6666665219) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 921037 + ... + 928246.

It is an arithmetic number, because the mean of its divisors is an integer number (576976608).

Almost surely, 2^6666665215 is an apocalyptic number.

6666665215 is a deficient number, since it is larger than the sum of its proper divisors (2564960513).

6666665215 is a wasteful number, since it uses less digits than its factorization.

6666665215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1849398.

The product of its digits is 2332800, while the sum is 49.

The square root of 6666665215 is about 81649.6492031656. The cubic root of 6666665215 is about 1882.0719211550.

The spelling of 6666665215 in words is "six billion, six hundred sixty-six million, six hundred sixty-five thousand, two hundred fifteen".