12120111121 has 4 divisors (see below), whose sum is σ = 12833058852. Its totient is φ = 11407163392.

The previous prime is 12120111109. The next prime is 12120111149. The reversal of 12120111121 is 12111102121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12111102121 = 313 ⋅38693617.

It can be written as a sum of positive squares in 2 ways, for example, as 9208321600 + 2911789521 = 95960^2 + 53961^2 .

It is a cyclic number.

It is not a de Polignac number, because 12120111121 - 2²⁷ = 11985893393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12120111151) 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, 356473840 + ... + 356473873.

It is an arithmetic number, because the mean of its divisors is an integer number (3208264713).

Almost surely, 2^12120111121 is an apocalyptic number.

It is an amenable number.

12120111121 is a deficient number, since it is larger than the sum of its proper divisors (712947731).

12120111121 is an equidigital number, since it uses as much as digits as its factorization.

12120111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712947730.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 12120111121 its reverse (12111102121), we get a palindrome (24231213242).

The spelling of 12120111121 in words is "twelve billion, one hundred twenty million, one hundred eleven thousand, one hundred twenty-one".