6644865 has 8 divisors (see below), whose sum is σ = 10631808. Its totient is φ = 3543920.

The previous prime is 6644863. The next prime is 6644873. The reversal of 6644865 is 5684466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6644865 - 2¹ = 6644863 is a prime.

It is a d-powerful number, because it can be written as 6² + 6⁵ + 4⁸ + 4¹¹ + 8⁷ + 6⁷ + 5³ .

It is not an unprimeable number, because it can be changed into a prime (6644863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 221481 + ... + 221510.

It is an arithmetic number, because the mean of its divisors is an integer number (1328976).

Almost surely, 2^6644865 is an apocalyptic number.

It is an amenable number.

6644865 is a deficient number, since it is larger than the sum of its proper divisors (3986943).

6644865 is a wasteful number, since it uses less digits than its factorization.

6644865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 442999.

The product of its digits is 138240, while the sum is 39.

The square root of 6644865 is about 2577.7635655738. The cubic root of 6644865 is about 188.0018201876.

The spelling of 6644865 in words is "six million, six hundred forty-four thousand, eight hundred sixty-five".