115057721 has 2 divisors, whose sum is σ = 115057722. Its totient is φ = 115057720.

The previous prime is 115057699. The next prime is 115057741. The reversal of 115057721 is 127750511.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 107412496 + 7645225 = 10364^2 + 2765^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115057721 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (115057741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57528860 + 57528861.

It is an arithmetic number, because the mean of its divisors is an integer number (57528861).

Almost surely, 2^115057721 is an apocalyptic number.

It is an amenable number.

115057721 is a deficient number, since it is larger than the sum of its proper divisors (1).

115057721 is an equidigital number, since it uses as much as digits as its factorization.

115057721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2450, while the sum is 29.

The square root of 115057721 is about 10726.4962126502. The cubic root of 115057721 is about 486.3757600802.

The spelling of 115057721 in words is "one hundred fifteen million, fifty-seven thousand, seven hundred twenty-one".