25660154312081 has 2 divisors, whose sum is σ = 25660154312082. Its totient is φ = 25660154312080.

The previous prime is 25660154311973. The next prime is 25660154312087. The reversal of 25660154312081 is 18021345106652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17107190855056 + 8552963457025 = 4136084^2 + 2924545^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25660154312081 is a prime.

It is a super-2 number, since 2×25660154312081² (a number of 28 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (25660154312087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12830077156040 + 12830077156041.

It is an arithmetic number, because the mean of its divisors is an integer number (12830077156041).

Almost surely, 2^{25660154312081} is an apocalyptic number.

It is an amenable number.

25660154312081 is a deficient number, since it is larger than the sum of its proper divisors (1).

25660154312081 is an equidigital number, since it uses as much as digits as its factorization.

25660154312081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 345600, while the sum is 44.

The spelling of 25660154312081 in words is "twenty-five trillion, six hundred sixty billion, one hundred fifty-four million, three hundred twelve thousand, eighty-one".