25491439 has 2 divisors, whose sum is σ = 25491440. Its totient is φ = 25491438.

The previous prime is 25491397. The next prime is 25491443. The reversal of 25491439 is 93419452.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25491439 - 2⁷ = 25491311 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 25491398 and 25491407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25491139) 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, 12745719 + 12745720.

It is an arithmetic number, because the mean of its divisors is an integer number (12745720).

Almost surely, 2^25491439 is an apocalyptic number.

25491439 is a deficient number, since it is larger than the sum of its proper divisors (1).

25491439 is an equidigital number, since it uses as much as digits as its factorization.

25491439 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 37.

The square root of 25491439 is about 5048.9047327118. The cubic root of 25491439 is about 294.3053232045.

The spelling of 25491439 in words is "twenty-five million, four hundred ninety-one thousand, four hundred thirty-nine".