11820981155 has 4 divisors (see below), whose sum is σ = 14185177392. Its totient is φ = 9456784920.

The previous prime is 11820981083. The next prime is 11820981187. The reversal of 11820981155 is 55118902811.

11820981155 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a de Polignac number, because none of the positive numbers 2^k-11820981155 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1182098111 + ... + 1182098120.

It is an arithmetic number, because the mean of its divisors is an integer number (3546294348).

Almost surely, 2^11820981155 is an apocalyptic number.

11820981155 is a deficient number, since it is larger than the sum of its proper divisors (2364196237).

11820981155 is an equidigital number, since it uses as much as digits as its factorization.

11820981155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2364196236.

The product of its (nonzero) digits is 28800, while the sum is 41.

The spelling of 11820981155 in words is "eleven billion, eight hundred twenty million, nine hundred eighty-one thousand, one hundred fifty-five".