115785598199021 has 4 divisors (see below), whose sum is σ = 119778205033500. Its totient is φ = 111792991364544.

The previous prime is 115785598198997. The next prime is 115785598199053. The reversal of 115785598199021 is 120991895587511.

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

It can be written as a sum of positive squares in 2 ways, for example, as 78727467122500 + 37058131076521 = 8872850^2 + 6087539^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115785598199021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115785598199071) 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, 1996303417196 + ... + 1996303417253.

It is an arithmetic number, because the mean of its divisors is an integer number (29944551258375).

Almost surely, 2^{115785598199021} is an apocalyptic number.

It is an amenable number.

115785598199021 is a deficient number, since it is larger than the sum of its proper divisors (3992606834479).

115785598199021 is an equidigital number, since it uses as much as digits as its factorization.

115785598199021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3992606834478.

The product of its (nonzero) digits is 81648000, while the sum is 71.

The spelling of 115785598199021 in words is "one hundred fifteen trillion, seven hundred eighty-five billion, five hundred ninety-eight million, one hundred ninety-nine thousand, twenty-one".