6646865 has 32 divisors (see below), whose sum is σ = 9047040. Its totient is φ = 4665600.

The previous prime is 6646859. The next prime is 6646867. The reversal of 6646865 is 5686466.

It is not a de Polignac number, because 6646865 - 2²⁰ = 5598289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6646867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 108935 + ... + 108995.

It is an arithmetic number, because the mean of its divisors is an integer number (282720).

Almost surely, 2^6646865 is an apocalyptic number.

It is an amenable number.

6646865 is a deficient number, since it is larger than the sum of its proper divisors (2400175).

6646865 is a wasteful number, since it uses less digits than its factorization.

6646865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153.

The product of its digits is 207360, while the sum is 41.

The square root of 6646865 is about 2578.1514695611. The cubic root of 6646865 is about 188.0206801606.

The spelling of 6646865 in words is "six million, six hundred forty-six thousand, eight hundred sixty-five".