25391813 has 2 divisors, whose sum is σ = 25391814. Its totient is φ = 25391812.

The previous prime is 25391783. The next prime is 25391827. The reversal of 25391813 is 31819352.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21883684 + 3508129 = 4678^2 + 1873^2 .

It is a cyclic number.

It is not a de Polignac number, because 25391813 - 2¹² = 25387717 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 25391813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25391843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12695906 + 12695907.

It is an arithmetic number, because the mean of its divisors is an integer number (12695907).

Almost surely, 2^25391813 is an apocalyptic number.

It is an amenable number.

25391813 is a deficient number, since it is larger than the sum of its proper divisors (1).

25391813 is an equidigital number, since it uses as much as digits as its factorization.

25391813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 32.

The square root of 25391813 is about 5039.0289739195. The cubic root of 25391813 is about 293.9214199110.

The spelling of 25391813 in words is "twenty-five million, three hundred ninety-one thousand, eight hundred thirteen".