12112012021 has 4 divisors (see below), whose sum is σ = 12117983500. Its totient is φ = 12106040544.

The previous prime is 12112012019. The next prime is 12112012043. The reversal of 12112012021 is 12021021121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12021021121 = 36857 ⋅326153.

It can be written as a sum of positive squares in 2 ways, for example, as 7966455025 + 4145556996 = 89255^2 + 64386^2 .

It is a cyclic number.

It is not a de Polignac number, because 12112012021 - 2¹ = 12112012019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12112011992 and 12112012010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12112012051) 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, 2982696 + ... + 2986753.

It is an arithmetic number, because the mean of its divisors is an integer number (3029495875).

Almost surely, 2^12112012021 is an apocalyptic number.

It is an amenable number.

12112012021 is a deficient number, since it is larger than the sum of its proper divisors (5971479).

12112012021 is an equidigital number, since it uses as much as digits as its factorization.

12112012021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5971478.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 12112012021 its reverse (12021021121), we get a palindrome (24133033142).

The spelling of 12112012021 in words is "twelve billion, one hundred twelve million, twelve thousand, twenty-one".