25655572517 has 2 divisors, whose sum is σ = 25655572518. Its totient is φ = 25655572516.

The previous prime is 25655572513. The next prime is 25655572549. The reversal of 25655572517 is 71527555652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16945270276 + 8710302241 = 130174^2 + 93329^2 .

It is a cyclic number.

It is not a de Polignac number, because 25655572517 - 2² = 25655572513 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25655572513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12827786258 + 12827786259.

It is an arithmetic number, because the mean of its divisors is an integer number (12827786259).

Almost surely, 2^25655572517 is an apocalyptic number.

It is an amenable number.

25655572517 is a deficient number, since it is larger than the sum of its proper divisors (1).

25655572517 is an equidigital number, since it uses as much as digits as its factorization.

25655572517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3675000, while the sum is 50.

The spelling of 25655572517 in words is "twenty-five billion, six hundred fifty-five million, five hundred seventy-two thousand, five hundred seventeen".