25603909 has 2 divisors, whose sum is σ = 25603910. Its totient is φ = 25603908.

The previous prime is 25603901. The next prime is 25603913. The reversal of 25603909 is 90930652.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23794884 + 1809025 = 4878^2 + 1345^2 .

It is a cyclic number.

It is not a de Polignac number, because 25603909 - 2³ = 25603901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25603901) 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, 12801954 + 12801955.

It is an arithmetic number, because the mean of its divisors is an integer number (12801955).

Almost surely, 2^25603909 is an apocalyptic number.

It is an amenable number.

25603909 is a deficient number, since it is larger than the sum of its proper divisors (1).

25603909 is an equidigital number, since it uses as much as digits as its factorization.

25603909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 34.

The square root of 25603909 is about 5060.0305335047. The cubic root of 25603909 is about 294.7375200435.

The spelling of 25603909 in words is "twenty-five million, six hundred three thousand, nine hundred nine".