115532721 has 12 divisors (see below), whose sum is σ = 170431872. Its totient is φ = 75382776.

The previous prime is 115532717. The next prime is 115532743. The reversal of 115532721 is 127235511.

It is not a de Polignac number, because 115532721 - 2² = 115532717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (115532761) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 136141 + ... + 136986.

It is an arithmetic number, because the mean of its divisors is an integer number (14202656).

Almost surely, 2^115532721 is an apocalyptic number.

It is an amenable number.

115532721 is a deficient number, since it is larger than the sum of its proper divisors (54899151).

115532721 is a wasteful number, since it uses less digits than its factorization.

115532721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273180 (or 273177 counting only the distinct ones).

The product of its digits is 2100, while the sum is 27.

The square root of 115532721 is about 10748.6148409923. The cubic root of 115532721 is about 487.0441529763.

The spelling of 115532721 in words is "one hundred fifteen million, five hundred thirty-two thousand, seven hundred twenty-one".