25656559 has 2 divisors, whose sum is σ = 25656560. Its totient is φ = 25656558.

The previous prime is 25656551. The next prime is 25656581. The reversal of 25656559 is 95565652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25656559 - 2³ = 25656551 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25656551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12828279 + 12828280.

It is an arithmetic number, because the mean of its divisors is an integer number (12828280).

Almost surely, 2^25656559 is an apocalyptic number.

25656559 is a deficient number, since it is larger than the sum of its proper divisors (1).

25656559 is an equidigital number, since it uses as much as digits as its factorization.

25656559 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 405000, while the sum is 43.

The square root of 25656559 is about 5065.2303994981. The cubic root of 25656559 is about 294.9394072621.

The spelling of 25656559 in words is "twenty-five million, six hundred fifty-six thousand, five hundred fifty-nine".