25643613 has 4 divisors (see below), whose sum is σ = 34191488. Its totient is φ = 17095740.

The previous prime is 25643593. The next prime is 25643621. The reversal of 25643613 is 31634652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 25643613 - 2⁵ = 25643581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25643663) 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 3 ways as a sum of consecutive naturals, for example, 4273933 + ... + 4273938.

It is an arithmetic number, because the mean of its divisors is an integer number (8547872).

Almost surely, 2^25643613 is an apocalyptic number.

It is an amenable number.

25643613 is a deficient number, since it is larger than the sum of its proper divisors (8547875).

25643613 is an equidigital number, since it uses as much as digits as its factorization.

25643613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8547874.

The product of its digits is 12960, while the sum is 30.

The square root of 25643613 is about 5063.9523102020. The cubic root of 25643613 is about 294.8897912560.

The spelling of 25643613 in words is "twenty-five million, six hundred forty-three thousand, six hundred thirteen".