115251991 has 2 divisors, whose sum is σ = 115251992. Its totient is φ = 115251990.

The previous prime is 115251979. The next prime is 115252001. The reversal of 115251991 is 199152511.

It is a strong prime.

It is an emirp because it is prime and its reverse (199152511) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 115251991 - 2⁷ = 115251863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (115251901) 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, 57625995 + 57625996.

It is an arithmetic number, because the mean of its divisors is an integer number (57625996).

Almost surely, 2^115251991 is an apocalyptic number.

115251991 is a deficient number, since it is larger than the sum of its proper divisors (1).

115251991 is an equidigital number, since it uses as much as digits as its factorization.

115251991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4050, while the sum is 34.

The square root of 115251991 is about 10735.5480065062. The cubic root of 115251991 is about 486.6493476562.

The spelling of 115251991 in words is "one hundred fifteen million, two hundred fifty-one thousand, nine hundred ninety-one".