12123111121 has 12 divisors (see below), whose sum is σ = 13385188096. Its totient is φ = 10971564120.

The previous prime is 12123111113. The next prime is 12123111167. The reversal of 12123111121 is 12111132121.

It is a happy number.

It is not a de Polignac number, because 12123111121 - 2³ = 12123111113 is a prime.

It is a super-2 number, since 2×12123111121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12123111095 and 12123111104.

It is not an unprimeable number, because it can be changed into a prime (12123111421) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 197661 + ... + 251626.

Almost surely, 2^12123111121 is an apocalyptic number.

12123111121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12123111121 is a deficient number, since it is larger than the sum of its proper divisors (1262076975).

12123111121 is a wasteful number, since it uses less digits than its factorization.

12123111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449532 (or 449521 counting only the distinct ones).

The product of its digits is 24, while the sum is 16.

Adding to 12123111121 its reverse (12111132121), we get a palindrome (24234243242).

The spelling of 12123111121 in words is "twelve billion, one hundred twenty-three million, one hundred eleven thousand, one hundred twenty-one".