6445865 has 12 divisors (see below), whose sum is σ = 8089284. Its totient is φ = 4930464.

The previous prime is 6445853. The next prime is 6445871. The reversal of 6445865 is 5685446.

It can be written as a sum of positive squares in 2 ways, for example, as 4477456 + 1968409 = 2116^2 + 1403^2 .

It is not a de Polignac number, because 6445865 - 2⁴ = 6445849 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 1427 + ... + 3863.

It is an arithmetic number, because the mean of its divisors is an integer number (674107).

Almost surely, 2^6445865 is an apocalyptic number.

It is an amenable number.

6445865 is a deficient number, since it is larger than the sum of its proper divisors (1643419).

6445865 is a wasteful number, since it uses less digits than its factorization.

6445865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2488 (or 2465 counting only the distinct ones).

The product of its digits is 115200, while the sum is 38.

The square root of 6445865 is about 2538.8708119950. The cubic root of 6445865 is about 186.1060115597.

The spelling of 6445865 in words is "six million, four hundred forty-five thousand, eight hundred sixty-five".