115721251 has 2 divisors, whose sum is σ = 115721252. Its totient is φ = 115721250.

The previous prime is 115721231. The next prime is 115721273. The reversal of 115721251 is 152127511.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 115721251 - 2⁹ = 115720739 is a prime.

It is not a weakly prime, because it can be changed into another prime (115721231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57860625 + 57860626.

It is an arithmetic number, because the mean of its divisors is an integer number (57860626).

Almost surely, 2^115721251 is an apocalyptic number.

115721251 is a deficient number, since it is larger than the sum of its proper divisors (1).

115721251 is an equidigital number, since it uses as much as digits as its factorization.

115721251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 700, while the sum is 25.

The square root of 115721251 is about 10757.3812333672. The cubic root of 115721251 is about 487.3089337597.

Adding to 115721251 its reverse (152127511), we get a palindrome (267848762).

The spelling of 115721251 in words is "one hundred fifteen million, seven hundred twenty-one thousand, two hundred fifty-one".