6659865 has 12 divisors (see below), whose sum is σ = 11543844. Its totient is φ = 3551904.

The previous prime is 6659843. The next prime is 6659893. The reversal of 6659865 is 5689566.

It can be written as a sum of positive squares in 2 ways, for example, as 4309776 + 2350089 = 2076^2 + 1533^2 .

It is not a de Polignac number, because 6659865 - 2⁵ = 6659833 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 147997 = 6659865 / (6 + 6 + 5 + 9 + 8 + 6 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 6659865.

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 11 ways as a sum of consecutive naturals, for example, 73954 + ... + 74043.

It is an arithmetic number, because the mean of its divisors is an integer number (961987).

Almost surely, 2^6659865 is an apocalyptic number.

It is an amenable number.

6659865 is a deficient number, since it is larger than the sum of its proper divisors (4883979).

6659865 is a wasteful number, since it uses less digits than its factorization.

6659865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148008 (or 148005 counting only the distinct ones).

The product of its digits is 388800, while the sum is 45.

The square root of 6659865 is about 2580.6714242615. The cubic root of 6659865 is about 188.1431778625.

Subtracting from 6659865 its reverse (5689566), we obtain a cube (970299 = 99³).

The spelling of 6659865 in words is "six million, six hundred fifty-nine thousand, eight hundred sixty-five".