115221691 has 4 divisors (see below), whose sum is σ = 124084912. Its totient is φ = 106358472.

The previous prime is 115221683. The next prime is 115221703. The reversal of 115221691 is 196122511.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 115221691 - 2³ = 115221683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (115221641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4431591 + ... + 4431616.

It is an arithmetic number, because the mean of its divisors is an integer number (31021228).

Almost surely, 2^115221691 is an apocalyptic number.

115221691 is a deficient number, since it is larger than the sum of its proper divisors (8863221).

115221691 is an equidigital number, since it uses as much as digits as its factorization.

115221691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8863220.

The product of its digits is 1080, while the sum is 28.

The square root of 115221691 is about 10734.1367142402. The cubic root of 115221691 is about 486.6066968598.

The spelling of 115221691 in words is "one hundred fifteen million, two hundred twenty-one thousand, six hundred ninety-one".