25861909 has 2 divisors, whose sum is σ = 25861910. Its totient is φ = 25861908.

The previous prime is 25861873. The next prime is 25861931. The reversal of 25861909 is 90916852.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24039409 + 1822500 = 4903^2 + 1350^2 .

It is a cyclic number.

It is not a de Polignac number, because 25861909 - 2¹¹ = 25859861 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25861949) 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 as a sum of consecutive naturals, namely, 12930954 + 12930955.

It is an arithmetic number, because the mean of its divisors is an integer number (12930955).

Almost surely, 2^25861909 is an apocalyptic number.

It is an amenable number.

25861909 is a deficient number, since it is larger than the sum of its proper divisors (1).

25861909 is an equidigital number, since it uses as much as digits as its factorization.

25861909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 25861909 is about 5085.4605494488. The cubic root of 25861909 is about 295.7241960096.

The spelling of 25861909 in words is "twenty-five million, eight hundred sixty-one thousand, nine hundred nine".