25403609 has 16 divisors (see below), whose sum is σ = 32323200. Its totient is φ = 19792080.

The previous prime is 25403563. The next prime is 25403671. The reversal of 25403609 is 90630452.

It is a de Polignac number, because none of the positive numbers 2^k-25403609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25403309) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 407 + ... + 7139.

It is an arithmetic number, because the mean of its divisors is an integer number (2020200).

Almost surely, 2^25403609 is an apocalyptic number.

It is an amenable number.

25403609 is a deficient number, since it is larger than the sum of its proper divisors (6919591).

25403609 is an equidigital number, since it uses as much as digits as its factorization.

25403609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6765 (or 6751 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 25403609 is about 5040.1993016150. The cubic root of 25403609 is about 293.9669274967.

The spelling of 25403609 in words is "twenty-five million, four hundred three thousand, six hundred nine".