115995991 has 4 divisors (see below), whose sum is σ = 116048872. Its totient is φ = 115943112.

The previous prime is 115995977. The next prime is 115996003. The reversal of 115995991 is 199599511.

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 115995991 - 2⁷ = 115995863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115995941) 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, 23001 + ... + 27586.

It is an arithmetic number, because the mean of its divisors is an integer number (29012218).

Almost surely, 2^115995991 is an apocalyptic number.

115995991 is a deficient number, since it is larger than the sum of its proper divisors (52881).

115995991 is an equidigital number, since it uses as much as digits as its factorization.

115995991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52880.

The product of its digits is 164025, while the sum is 49.

The square root of 115995991 is about 10770.1434995083. The cubic root of 115995991 is about 487.6942776837.

The spelling of 115995991 in words is "one hundred fifteen million, nine hundred ninety-five thousand, nine hundred ninety-one".