12021111121 has 4 divisors (see below), whose sum is σ = 12653801200. Its totient is φ = 11388421044.

The previous prime is 12021111073. The next prime is 12021111133. The reversal of 12021111121 is 12111112021.

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 an emirpimes, since its reverse is a distinct semiprime: 12111112021 = 103451 ⋅117071.

It is a cyclic number.

It is not a de Polignac number, because 12021111121 - 2¹¹ = 12021109073 is a prime.

It is a super-2 number, since 2×12021111121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12021111191) 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, 316345011 + ... + 316345048.

It is an arithmetic number, because the mean of its divisors is an integer number (3163450300).

Almost surely, 2^12021111121 is an apocalyptic number.

It is an amenable number.

12021111121 is a deficient number, since it is larger than the sum of its proper divisors (632690079).

12021111121 is an equidigital number, since it uses as much as digits as its factorization.

12021111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 632690078.

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

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

The spelling of 12021111121 in words is "twelve billion, twenty-one million, one hundred eleven thousand, one hundred twenty-one".