111121221121 has 4 divisors (see below), whose sum is σ = 112200068032. Its totient is φ = 110042374212.

The previous prime is 111121221007. The next prime is 111121221161. The reversal of 111121221121 is 121122121111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 121122121111 = 2719 ⋅44546569.

It is a cyclic number.

It is not a de Polignac number, because 111121221121 - 2¹⁹ = 111120696833 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111121221095 and 111121221104.

It is not an unprimeable number, because it can be changed into a prime (111121221161) 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, 539423301 + ... + 539423506.

It is an arithmetic number, because the mean of its divisors is an integer number (28050017008).

Almost surely, 2^111121221121 is an apocalyptic number.

It is an amenable number.

111121221121 is a deficient number, since it is larger than the sum of its proper divisors (1078846911).

111121221121 is a wasteful number, since it uses less digits than its factorization.

111121221121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1078846910.

The product of its digits is 16, while the sum is 16.

Adding to 111121221121 its reverse (121122121111), we get a palindrome (232243342232).

The spelling of 111121221121 in words is "one hundred eleven billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred twenty-one".