6665865 has 24 divisors (see below), whose sum is σ = 11265408. Its totient is φ = 3365280.

The previous prime is 6665861. The next prime is 6665873. The reversal of 6665865 is 5685666.

It is not a de Polignac number, because 6665865 - 2² = 6665861 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6665861) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4800 + ... + 6030.

It is an arithmetic number, because the mean of its divisors is an integer number (469392).

Almost surely, 2^6665865 is an apocalyptic number.

It is an amenable number.

6665865 is a deficient number, since it is larger than the sum of its proper divisors (4599543).

6665865 is a wasteful number, since it uses less digits than its factorization.

6665865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277 (or 1258 counting only the distinct ones).

The product of its digits is 259200, while the sum is 42.

The square root of 6665865 is about 2581.8336507219. The cubic root of 6665865 is about 188.1996615016.

The spelling of 6665865 in words is "six million, six hundred sixty-five thousand, eight hundred sixty-five".