25661252543 has 2 divisors, whose sum is σ = 25661252544. Its totient is φ = 25661252542.

The previous prime is 25661252501. The next prime is 25661252549. The reversal of 25661252543 is 34525216652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25661252543 - 2²⁰ = 25660203967 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25661252543.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25661252549) 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, 12830626271 + 12830626272.

It is an arithmetic number, because the mean of its divisors is an integer number (12830626272).

Almost surely, 2^25661252543 is an apocalyptic number.

25661252543 is a deficient number, since it is larger than the sum of its proper divisors (1).

25661252543 is an equidigital number, since it uses as much as digits as its factorization.

25661252543 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432000, while the sum is 41.

The spelling of 25661252543 in words is "twenty-five billion, six hundred sixty-one million, two hundred fifty-two thousand, five hundred forty-three".