115717221 has 16 divisors (see below), whose sum is σ = 177345600. Its totient is φ = 74484144.

The previous prime is 115717219. The next prime is 115717229. The reversal of 115717221 is 122717511.

115717221 is a `hidden beast` number, since 1 + 1 + 571 + 72 + 21 = 666.

It is not a de Polignac number, because 115717221 - 2¹ = 115717219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115717229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 73111 + ... + 74676.

It is an arithmetic number, because the mean of its divisors is an integer number (11084100).

Almost surely, 2^115717221 is an apocalyptic number.

It is an amenable number.

115717221 is a deficient number, since it is larger than the sum of its proper divisors (61628379).

115717221 is a wasteful number, since it uses less digits than its factorization.

115717221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147825 (or 147819 counting only the distinct ones).

The product of its digits is 980, while the sum is 27.

The square root of 115717221 is about 10757.1939184901. The cubic root of 115717221 is about 487.3032768391.

The spelling of 115717221 in words is "one hundred fifteen million, seven hundred seventeen thousand, two hundred twenty-one".