25606979081 has 2 divisors, whose sum is σ = 25606979082. Its totient is φ = 25606979080.

The previous prime is 25606979077. The next prime is 25606979213. The reversal of 25606979081 is 18097960652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19075753225 + 6531225856 = 138115^2 + 80816^2 .

It is a cyclic number.

It is not a de Polignac number, because 25606979081 - 2² = 25606979077 is a prime.

It is a super-2 number, since 2×25606979081² (a number of 22 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 (25606979581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12803489540 + 12803489541.

It is an arithmetic number, because the mean of its divisors is an integer number (12803489541).

Almost surely, 2^25606979081 is an apocalyptic number.

It is an amenable number.

25606979081 is a deficient number, since it is larger than the sum of its proper divisors (1).

25606979081 is an equidigital number, since it uses as much as digits as its factorization.

25606979081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1632960, while the sum is 53.

The spelling of 25606979081 in words is "twenty-five billion, six hundred six million, nine hundred seventy-nine thousand, eighty-one".