123211111121 has 4 divisors (see below), whose sum is σ = 140812698432. Its totient is φ = 105609523812.

The previous prime is 123211111109. The next prime is 123211111129. The reversal of 123211111121 is 121111112321.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123211111121 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 123211111121.

It is not an unprimeable number, because it can be changed into a prime (123211111129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8800793645 + ... + 8800793658.

It is an arithmetic number, because the mean of its divisors is an integer number (35203174608).

Almost surely, 2^123211111121 is an apocalyptic number.

It is an amenable number.

123211111121 is a deficient number, since it is larger than the sum of its proper divisors (17601587311).

123211111121 is an equidigital number, since it uses as much as digits as its factorization.

123211111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17601587310.

The product of its digits is 24, while the sum is 17.

Adding to 123211111121 its reverse (121111112321), we get a palindrome (244322223442).

The spelling of 123211111121 in words is "one hundred twenty-three billion, two hundred eleven million, one hundred eleven thousand, one hundred twenty-one".