111111122221211 has 4 divisors (see below), whose sum is σ = 126984139681392. Its totient is φ = 95238104761032.

The previous prime is 111111122221181. The next prime is 111111122221343. The reversal of 111111122221211 is 112122221111111.

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 111111122221211 - 2¹⁰ = 111111122220187 is a prime.

It is not an unprimeable number, because it can be changed into a prime (111111122220211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7936508730080 + ... + 7936508730093.

It is an arithmetic number, because the mean of its divisors is an integer number (31746034920348).

Almost surely, 2^{111111122221211} is an apocalyptic number.

111111122221211 is a deficient number, since it is larger than the sum of its proper divisors (15873017460181).

111111122221211 is an equidigital number, since it uses as much as digits as its factorization.

111111122221211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15873017460180.

The product of its digits is 32, while the sum is 20.

Adding to 111111122221211 its reverse (112122221111111), we get a palindrome (223233343332322).

The spelling of 111111122221211 in words is "one hundred eleven trillion, one hundred eleven billion, one hundred twenty-two million, two hundred twenty-one thousand, two hundred eleven".