11981154091 has 4 divisors (see below), whose sum is σ = 11984541184. Its totient is φ = 11977767000.

The previous prime is 11981154049. The next prime is 11981154151. The reversal of 11981154091 is 19045118911.

11981154091 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 cyclic number.

It is not a de Polignac number, because 11981154091 - 2⁷ = 11981153963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11981157091) by changing a digit.

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, 1688235 + ... + 1695316.

It is an arithmetic number, because the mean of its divisors is an integer number (2996135296).

Almost surely, 2^11981154091 is an apocalyptic number.

11981154091 is a deficient number, since it is larger than the sum of its proper divisors (3387093).

11981154091 is an equidigital number, since it uses as much as digits as its factorization.

11981154091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3387092.

The product of its (nonzero) digits is 12960, while the sum is 40.

The spelling of 11981154091 in words is "eleven billion, nine hundred eighty-one million, one hundred fifty-four thousand, ninety-one".