115717721 has 8 divisors (see below), whose sum is σ = 133137600. Its totient is φ = 98520048.

The previous prime is 115717697. The next prime is 115717727. The reversal of 115717721 is 127717511.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115717721 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (115717727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54431 + ... + 56516.

It is an arithmetic number, because the mean of its divisors is an integer number (16642200).

Almost surely, 2^115717721 is an apocalyptic number.

It is an amenable number.

115717721 is a deficient number, since it is larger than the sum of its proper divisors (17419879).

115717721 is a wasteful number, since it uses less digits than its factorization.

115717721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111103.

The product of its digits is 3430, while the sum is 32.

The square root of 115717721 is about 10757.2171587265. The cubic root of 115717721 is about 487.3039786974.

The spelling of 115717721 in words is "one hundred fifteen million, seven hundred seventeen thousand, seven hundred twenty-one".