12111112021 has 4 divisors (see below), whose sum is σ = 12111332544. Its totient is φ = 12110891500.

The previous prime is 12111112007. The next prime is 12111112033. The reversal of 12111112021 is 12021111121.

It is a happy number.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12021111121 = 19 ⋅632690059.

It is a cyclic number.

It is not a de Polignac number, because 12111112021 - 2¹⁹ = 12110587733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12111111992 and 12111112010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12111112121) 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, 44916 + ... + 161986.

It is an arithmetic number, because the mean of its divisors is an integer number (3027833136).

Almost surely, 2^12111112021 is an apocalyptic number.

It is an amenable number.

12111112021 is a deficient number, since it is larger than the sum of its proper divisors (220523).

12111112021 is a wasteful number, since it uses less digits than its factorization.

12111112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220522.

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

Adding to 12111112021 its reverse (12021111121), we get a palindrome (24132223142).

The spelling of 12111112021 in words is "twelve billion, one hundred eleven million, one hundred twelve thousand, twenty-one".