2643865 has 8 divisors (see below), whose sum is σ = 3625920. Its totient is φ = 1812912.

The previous prime is 2643853. The next prime is 2643871. The reversal of 2643865 is 5683462.

It is a happy number.

2643865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 2643865 - 2⁵ = 2643833 is a prime.

2643865 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2643865.

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 7 ways as a sum of consecutive naturals, for example, 37735 + ... + 37804.

It is an arithmetic number, because the mean of its divisors is an integer number (453240).

2^2643865 is an apocalyptic number.

It is an amenable number.

2643865 is a deficient number, since it is larger than the sum of its proper divisors (982055).

2643865 is an equidigital number, since it uses as much as digits as its factorization.

2643865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75551.

The product of its digits is 34560, while the sum is 34.

The square root of 2643865 is about 1625.9966174627. The cubic root of 2643865 is about 138.2758781415.

The spelling of 2643865 in words is "two million, six hundred forty-three thousand, eight hundred sixty-five".