25231613261 has 2 divisors, whose sum is σ = 25231613262. Its totient is φ = 25231613260.

The previous prime is 25231613243. The next prime is 25231613263. The reversal of 25231613261 is 16231613252.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22984379236 + 2247234025 = 151606^2 + 47405^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25231613261 is a prime.

Together with 25231613263, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25231613263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12615806630 + 12615806631.

It is an arithmetic number, because the mean of its divisors is an integer number (12615806631).

Almost surely, 2^25231613261 is an apocalyptic number.

It is an amenable number.

25231613261 is a deficient number, since it is larger than the sum of its proper divisors (1).

25231613261 is an equidigital number, since it uses as much as digits as its factorization.

25231613261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 32.

Subtracting from 25231613261 its reverse (16231613252), we obtain a palindrome (9000000009).

The spelling of 25231613261 in words is "twenty-five billion, two hundred thirty-one million, six hundred thirteen thousand, two hundred sixty-one".