25261604497 has 2 divisors, whose sum is σ = 25261604498. Its totient is φ = 25261604496.

The previous prime is 25261604471. The next prime is 25261604549. The reversal of 25261604497 is 79440616252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24388756561 + 872847936 = 156169^2 + 29544^2 .

It is a cyclic number.

It is not a de Polignac number, because 25261604497 - 2¹¹ = 25261602449 is a prime.

It is not a weakly prime, because it can be changed into another prime (25261604447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12630802248 + 12630802249.

It is an arithmetic number, because the mean of its divisors is an integer number (12630802249).

Almost surely, 2^25261604497 is an apocalyptic number.

It is an amenable number.

25261604497 is a deficient number, since it is larger than the sum of its proper divisors (1).

25261604497 is an equidigital number, since it uses as much as digits as its factorization.

25261604497 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 725760, while the sum is 46.

The spelling of 25261604497 in words is "twenty-five billion, two hundred sixty-one million, six hundred four thousand, four hundred ninety-seven".