25561800443 has 2 divisors, whose sum is σ = 25561800444. Its totient is φ = 25561800442.

The previous prime is 25561800401. The next prime is 25561800469. The reversal of 25561800443 is 34400816552.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25561800443 - 2¹⁶ = 25561734907 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 25561800397 and 25561800406.

It is not a weakly prime, because it can be changed into another prime (25561800643) 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, 12780900221 + 12780900222.

It is an arithmetic number, because the mean of its divisors is an integer number (12780900222).

Almost surely, 2^25561800443 is an apocalyptic number.

25561800443 is a deficient number, since it is larger than the sum of its proper divisors (1).

25561800443 is an equidigital number, since it uses as much as digits as its factorization.

25561800443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 115200, while the sum is 38.

The spelling of 25561800443 in words is "twenty-five billion, five hundred sixty-one million, eight hundred thousand, four hundred forty-three".