25919357617 has 2 divisors, whose sum is σ = 25919357618. Its totient is φ = 25919357616.

The previous prime is 25919357533. The next prime is 25919357669. The reversal of 25919357617 is 71675391952.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14844741921 + 11074615696 = 121839^2 + 105236^2 .

It is a cyclic number.

It is not a de Polignac number, because 25919357617 - 2¹⁹ = 25918833329 is a prime.

It is not a weakly prime, because it can be changed into another prime (25919357117) 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, 12959678808 + 12959678809.

It is an arithmetic number, because the mean of its divisors is an integer number (12959678809).

Almost surely, 2^25919357617 is an apocalyptic number.

It is an amenable number.

25919357617 is a deficient number, since it is larger than the sum of its proper divisors (1).

25919357617 is an equidigital number, since it uses as much as digits as its factorization.

25919357617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3572100, while the sum is 55.

The spelling of 25919357617 in words is "twenty-five billion, nine hundred nineteen million, three hundred fifty-seven thousand, six hundred seventeen".