25105609 has 2 divisors, whose sum is σ = 25105610. Its totient is φ = 25105608.

The previous prime is 25105607. The next prime is 25105657. The reversal of 25105609 is 90650152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19360000 + 5745609 = 4400^2 + 2397^2 .

It is a cyclic number.

It is not a de Polignac number, because 25105609 - 2¹ = 25105607 is a prime.

Together with 25105607, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (25105601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12552804 + 12552805.

It is an arithmetic number, because the mean of its divisors is an integer number (12552805).

Almost surely, 2^25105609 is an apocalyptic number.

It is an amenable number.

25105609 is a deficient number, since it is larger than the sum of its proper divisors (1).

25105609 is an equidigital number, since it uses as much as digits as its factorization.

25105609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 25105609 is about 5010.5497702348. The cubic root of 25105609 is about 292.8129321891.

The spelling of 25105609 in words is "twenty-five million, one hundred five thousand, six hundred nine".