115550721 has 24 divisors (see below), whose sum is σ = 196088256. Its totient is φ = 64643040.

The previous prime is 115550719. The next prime is 115550731. The reversal of 115550721 is 127055511.

115550721 is a `hidden beast` number, since 1 + 155 + 507 + 2 + 1 = 666.

It is not a de Polignac number, because 115550721 - 2¹ = 115550719 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (115550711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43605 + ... + 46178.

It is an arithmetic number, because the mean of its divisors is an integer number (8170344).

Almost surely, 2^115550721 is an apocalyptic number.

115550721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

115550721 is a deficient number, since it is larger than the sum of its proper divisors (80537535).

115550721 is a wasteful number, since it uses less digits than its factorization.

115550721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89813 (or 89810 counting only the distinct ones).

The product of its (nonzero) digits is 1750, while the sum is 27.

The square root of 115550721 is about 10749.4521255737. The cubic root of 115550721 is about 487.0694454921.

The spelling of 115550721 in words is "one hundred fifteen million, five hundred fifty thousand, seven hundred twenty-one".