25697776813 has 2 divisors, whose sum is σ = 25697776814. Its totient is φ = 25697776812.

The previous prime is 25697776777. The next prime is 25697776829. The reversal of 25697776813 is 31867779652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25297856809 + 399920004 = 159053^2 + 19998^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25697776813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25697776613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12848888406 + 12848888407.

It is an arithmetic number, because the mean of its divisors is an integer number (12848888407).

Almost surely, 2^25697776813 is an apocalyptic number.

It is an amenable number.

25697776813 is a deficient number, since it is larger than the sum of its proper divisors (1).

25697776813 is an equidigital number, since it uses as much as digits as its factorization.

25697776813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26671680, while the sum is 61.

The spelling of 25697776813 in words is "twenty-five billion, six hundred ninety-seven million, seven hundred seventy-six thousand, eight hundred thirteen".