11991116611 has 4 divisors (see below), whose sum is σ = 12269979832. Its totient is φ = 11712253392.

The previous prime is 11991116573. The next prime is 11991116629. The reversal of 11991116611 is 11661119911.

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 11991116611 - 2⁷ = 11991116483 is a prime.

11991116611 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (11991116681) 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 3 ways as a sum of consecutive naturals, for example, 139431546 + ... + 139431631.

It is an arithmetic number, because the mean of its divisors is an integer number (3067494958).

Almost surely, 2^11991116611 is an apocalyptic number.

11991116611 is a deficient number, since it is larger than the sum of its proper divisors (278863221).

11991116611 is an equidigital number, since it uses as much as digits as its factorization.

11991116611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278863220.

The product of its digits is 2916, while the sum is 37.

The spelling of 11991116611 in words is "eleven billion, nine hundred ninety-one million, one hundred sixteen thousand, six hundred eleven".