25628609 has 4 divisors (see below), whose sum is σ = 25673604. Its totient is φ = 25583616.

The previous prime is 25628593. The next prime is 25628611. The reversal of 25628609 is 90682652.

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 13897984 + 11730625 = 3728^2 + 3425^2 .

It is a cyclic number.

It is not a de Polignac number, because 25628609 - 2⁴ = 25628593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25628689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21632 + ... + 22785.

It is an arithmetic number, because the mean of its divisors is an integer number (6418401).

Almost surely, 2^25628609 is an apocalyptic number.

It is an amenable number.

25628609 is a deficient number, since it is larger than the sum of its proper divisors (44995).

25628609 is an equidigital number, since it uses as much as digits as its factorization.

25628609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44994.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 25628609 is about 5062.4706418902. The cubic root of 25628609 is about 294.8322669953.

The spelling of 25628609 in words is "twenty-five million, six hundred twenty-eight thousand, six hundred nine".