25938506491 has 2 divisors, whose sum is σ = 25938506492. Its totient is φ = 25938506490.

The previous prime is 25938506471. The next prime is 25938506497. The reversal of 25938506491 is 19460583952.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25938506491 - 2⁹ = 25938505979 is a prime.

It is a super-2 number, since 2×25938506491² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25938506497) 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, 12969253245 + 12969253246.

It is an arithmetic number, because the mean of its divisors is an integer number (12969253246).

Almost surely, 2^25938506491 is an apocalyptic number.

25938506491 is a deficient number, since it is larger than the sum of its proper divisors (1).

25938506491 is an equidigital number, since it uses as much as digits as its factorization.

25938506491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2332800, while the sum is 52.

The spelling of 25938506491 in words is "twenty-five billion, nine hundred thirty-eight million, five hundred six thousand, four hundred ninety-one".