25591009 has 2 divisors, whose sum is σ = 25591010. Its totient is φ = 25591008.

The previous prime is 25591003. The next prime is 25591031. The reversal of 25591009 is 90019552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15171025 + 10419984 = 3895^2 + 3228^2 .

It is a cyclic number.

It is not a de Polignac number, because 25591009 - 2¹⁵ = 25558241 is a prime.

It is not a weakly prime, because it can be changed into another prime (25591003) 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, 12795504 + 12795505.

It is an arithmetic number, because the mean of its divisors is an integer number (12795505).

Almost surely, 2^25591009 is an apocalyptic number.

It is an amenable number.

25591009 is a deficient number, since it is larger than the sum of its proper divisors (1).

25591009 is an equidigital number, since it uses as much as digits as its factorization.

25591009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4050, while the sum is 31.

The square root of 25591009 is about 5058.7556770415. The cubic root of 25591009 is about 294.6880125936.

The spelling of 25591009 in words is "twenty-five million, five hundred ninety-one thousand, nine".