115981917161 has 20 divisors (see below), whose sum is σ = 127860042960. Its totient is φ = 105206126520.

The previous prime is 115981917131. The next prime is 115981917179. The reversal of 115981917161 is 161719189511.

It is not a de Polignac number, because 115981917161 - 2²² = 115977722857 is a prime.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (115981917131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6828866 + ... + 6845828.

It is an arithmetic number, because the mean of its divisors is an integer number (6393002148).

Almost surely, 2^115981917161 is an apocalyptic number.

115981917161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

115981917161 is a deficient number, since it is larger than the sum of its proper divisors (11878125799).

115981917161 is an frugal number, since it uses more digits than its factorization.

115981917161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17474 (or 17441 counting only the distinct ones).

The product of its digits is 136080, while the sum is 50.

The spelling of 115981917161 in words is "one hundred fifteen billion, nine hundred eighty-one million, nine hundred seventeen thousand, one hundred sixty-one".