121111121111 has 16 divisors (see below), whose sum is σ = 123042727296. Its totient is φ = 119196000000.

The previous prime is 121111121107. The next prime is 121111121113. The reversal of 121111121111 is 111121111121.

It is a cyclic number.

It is not a de Polignac number, because 121111121111 - 2² = 121111121107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121111121113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12227261 + ... + 12237161.

It is an arithmetic number, because the mean of its divisors is an integer number (7690170456).

Almost surely, 2^121111121111 is an apocalyptic number.

121111121111 is a deficient number, since it is larger than the sum of its proper divisors (1931606185).

121111121111 is a wasteful number, since it uses less digits than its factorization.

121111121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10714.

The product of its digits is 4, while the sum is 14.

Adding to 121111121111 its reverse (111121111121), we get a palindrome (232232232232).

It can be divided in two parts, 121111121 and 111, that multiplied together give a palindrome (13443334431).

The spelling of 121111121111 in words is "one hundred twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, one hundred eleven".