115945721 has 2 divisors, whose sum is σ = 115945722. Its totient is φ = 115945720.

The previous prime is 115945651. The next prime is 115945723. The reversal of 115945721 is 127549511.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79210000 + 36735721 = 8900^2 + 6061^2 .

It is a cyclic number.

It is not a de Polignac number, because 115945721 - 2²⁶ = 48836857 is a prime.

Together with 115945723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (115945723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57972860 + 57972861.

It is an arithmetic number, because the mean of its divisors is an integer number (57972861).

Almost surely, 2^115945721 is an apocalyptic number.

It is an amenable number.

115945721 is a deficient number, since it is larger than the sum of its proper divisors (1).

115945721 is an equidigital number, since it uses as much as digits as its factorization.

115945721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12600, while the sum is 35.

The square root of 115945721 is about 10767.8094801125. The cubic root of 115945721 is about 487.6238156687.

The spelling of 115945721 in words is "one hundred fifteen million, nine hundred forty-five thousand, seven hundred twenty-one".