25356509 has 2 divisors, whose sum is σ = 25356510. Its totient is φ = 25356508.

The previous prime is 25356497. The next prime is 25356523. The reversal of 25356509 is 90565352.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23863225 + 1493284 = 4885^2 + 1222^2 .

It is a cyclic number.

It is not a de Polignac number, because 25356509 - 2⁴ = 25356493 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 (25356559) 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, 12678254 + 12678255.

It is an arithmetic number, because the mean of its divisors is an integer number (12678255).

Almost surely, 2^25356509 is an apocalyptic number.

It is an amenable number.

25356509 is a deficient number, since it is larger than the sum of its proper divisors (1).

25356509 is an equidigital number, since it uses as much as digits as its factorization.

25356509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40500, while the sum is 35.

The square root of 25356509 is about 5035.5246995720. The cubic root of 25356509 is about 293.7851369468.

The spelling of 25356509 in words is "twenty-five million, three hundred fifty-six thousand, five hundred nine".