115819561 has 16 divisors (see below), whose sum is σ = 136463040. Its totient is φ = 96909120.

The previous prime is 115819553. The next prime is 115819579. The reversal of 115819561 is 165918511.

It is not a de Polignac number, because 115819561 - 2³ = 115819553 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 115819561.

It is not an unprimeable number, because it can be changed into a prime (115819961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58951 + ... + 60883.

It is an arithmetic number, because the mean of its divisors is an integer number (8528940).

Almost surely, 2^115819561 is an apocalyptic number.

115819561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

115819561 is a deficient number, since it is larger than the sum of its proper divisors (20643479).

115819561 is a wasteful number, since it uses less digits than its factorization.

115819561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2376.

The product of its digits is 10800, while the sum is 37.

The square root of 115819561 is about 10761.9496839560. The cubic root of 115819561 is about 487.4468910805.

The spelling of 115819561 in words is "one hundred fifteen million, eight hundred nineteen thousand, five hundred sixty-one".