25644813 has 16 divisors (see below), whose sum is σ = 36833280. Its totient is φ = 15818544.

The previous prime is 25644799. The next prime is 25644821. The reversal of 25644813 is 31844652.

It is not a de Polignac number, because 25644813 - 2¹⁴ = 25628429 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25644833) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 2781 + ... + 7682.

It is an arithmetic number, because the mean of its divisors is an integer number (2302080).

Almost surely, 2^25644813 is an apocalyptic number.

It is an amenable number.

25644813 is a deficient number, since it is larger than the sum of its proper divisors (11188467).

25644813 is a wasteful number, since it uses less digits than its factorization.

25644813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10528.

The product of its digits is 23040, while the sum is 33.

The square root of 25644813 is about 5064.0707933440. The cubic root of 25644813 is about 294.8943910008.

The spelling of 25644813 in words is "twenty-five million, six hundred forty-four thousand, eight hundred thirteen".