25800090991 has 2 divisors, whose sum is σ = 25800090992. Its totient is φ = 25800090990.

The previous prime is 25800090989. The next prime is 25800091087. The reversal of 25800090991 is 19909000852.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25800090991 - 2¹ = 25800090989 is a prime.

Together with 25800090989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25800090931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12900045495 + 12900045496.

It is an arithmetic number, because the mean of its divisors is an integer number (12900045496).

Almost surely, 2^25800090991 is an apocalyptic number.

25800090991 is a deficient number, since it is larger than the sum of its proper divisors (1).

25800090991 is an equidigital number, since it uses as much as digits as its factorization.

25800090991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58320, while the sum is 43.

The spelling of 25800090991 in words is "twenty-five billion, eight hundred million, ninety thousand, nine hundred ninety-one".