25549259881 has 2 divisors, whose sum is σ = 25549259882. Its totient is φ = 25549259880.

The previous prime is 25549259861. The next prime is 25549259909. The reversal of 25549259881 is 18895294552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25548825600 + 434281 = 159840^2 + 659^2 .

It is a cyclic number.

It is not a de Polignac number, because 25549259881 - 2⁵ = 25549259849 is a prime.

It is a super-2 number, since 2×25549259881² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25549259861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12774629940 + 12774629941.

It is an arithmetic number, because the mean of its divisors is an integer number (12774629941).

Almost surely, 2^25549259881 is an apocalyptic number.

It is an amenable number.

25549259881 is a deficient number, since it is larger than the sum of its proper divisors (1).

25549259881 is an equidigital number, since it uses as much as digits as its factorization.

25549259881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368000, while the sum is 58.

The spelling of 25549259881 in words is "twenty-five billion, five hundred forty-nine million, two hundred fifty-nine thousand, eight hundred eighty-one".