121111021111 has 4 divisors (see below), whose sum is σ = 127485285400. Its totient is φ = 114736756824.

The previous prime is 121111021093. The next prime is 121111021147. The reversal of 121111021111 is 111120111121.

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 121111021111 - 2⁵ = 121111021079 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121111021091 and 121111021100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121111021151) 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, 3187132116 + ... + 3187132153.

It is an arithmetic number, because the mean of its divisors is an integer number (31871321350).

Almost surely, 2^121111021111 is an apocalyptic number.

121111021111 is a deficient number, since it is larger than the sum of its proper divisors (6374264289).

121111021111 is an equidigital number, since it uses as much as digits as its factorization.

121111021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6374264288.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 121111021111 its reverse (111120111121), we get a palindrome (232231132232).

The spelling of 121111021111 in words is "one hundred twenty-one billion, one hundred eleven million, twenty-one thousand, one hundred eleven".