121111112121 has 16 divisors (see below), whose sum is σ = 177370967040. Its totient is φ = 73165522320.

The previous prime is 121111112107. The next prime is 121111112123. The reversal of 121111112121 is 121211111121.

It is not a de Polignac number, because 121111112121 - 2¹⁴ = 121111095737 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121111112121.

It is not an unprimeable number, because it can be changed into a prime (121111112123) 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 15 ways as a sum of consecutive naturals, for example, 46189045 + ... + 46191666.

It is an arithmetic number, because the mean of its divisors is an integer number (11085685440).

Almost surely, 2^121111112121 is an apocalyptic number.

It is an amenable number.

121111112121 is a deficient number, since it is larger than the sum of its proper divisors (56259854919).

121111112121 is a wasteful number, since it uses less digits than its factorization.

121111112121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92380756.

The product of its digits is 8, while the sum is 15.

Adding to 121111112121 its reverse (121211111121), we get a palindrome (242322223242).

The spelling of 121111112121 in words is "one hundred twenty-one billion, one hundred eleven million, one hundred twelve thousand, one hundred twenty-one".