2564645 has 4 divisors (see below), whose sum is σ = 3077580. Its totient is φ = 2051712.

The previous prime is 2564633. The next prime is 2564651. The reversal of 2564645 is 5464652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 982081 + 1582564 = 991^2 + 1258^2 .

It is a cyclic number.

It is not a de Polignac number, because 2564645 - 2¹² = 2560549 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256460 + ... + 256469.

It is an arithmetic number, because the mean of its divisors is an integer number (769395).

2^2564645 is an apocalyptic number.

It is an amenable number.

2564645 is a deficient number, since it is larger than the sum of its proper divisors (512935).

2564645 is an equidigital number, since it uses as much as digits as its factorization.

2564645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512934.

The product of its digits is 28800, while the sum is 32.

The square root of 2564645 is about 1601.4509046487. The cubic root of 2564645 is about 136.8807636418.

The spelling of 2564645 in words is "two million, five hundred sixty-four thousand, six hundred forty-five".