12123111321 has 24 divisors (see below), whose sum is σ = 18172967904. Its totient is φ = 8076179520.

The previous prime is 12123111293. The next prime is 12123111361. The reversal of 12123111321 is 12311132121.

It is not a de Polignac number, because 12123111321 - 2⁵ = 12123111289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12123111294 and 12123111303.

It is not an unprimeable number, because it can be changed into a prime (12123111361) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 329281 + ... + 364241.

It is an arithmetic number, because the mean of its divisors is an integer number (757206996).

Almost surely, 2^12123111321 is an apocalyptic number.

It is an amenable number.

12123111321 is a deficient number, since it is larger than the sum of its proper divisors (6049856583).

12123111321 is an equidigital number, since it uses as much as digits as its factorization.

12123111321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36403 (or 36391 counting only the distinct ones).

The product of its digits is 72, while the sum is 18.

Adding to 12123111321 its reverse (12311132121), we get a palindrome (24434243442).

The spelling of 12123111321 in words is "twelve billion, one hundred twenty-three million, one hundred eleven thousand, three hundred twenty-one".