12120212021 has 4 divisors (see below), whose sum is σ = 12122464812. Its totient is φ = 12117959232.

The previous prime is 12120212009. The next prime is 12120212051. The reversal of 12120212021 is 12021202121.

12120212021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12021202121 = 191 ⋅62938231.

It can be written as a sum of positive squares in 2 ways, for example, as 11514363025 + 605848996 = 107305^2 + 24614^2 .

It is a cyclic number.

It is not a de Polignac number, because 12120212021 - 2¹⁰ = 12120210997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12120211987 and 12120212005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12120212051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1118306 + ... + 1129091.

It is an arithmetic number, because the mean of its divisors is an integer number (3030616203).

Almost surely, 2^12120212021 is an apocalyptic number.

It is an amenable number.

12120212021 is a deficient number, since it is larger than the sum of its proper divisors (2252791).

12120212021 is an equidigital number, since it uses as much as digits as its factorization.

12120212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2252790.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 12120212021 its reverse (12021202121), we get a palindrome (24141414142).

The spelling of 12120212021 in words is "twelve billion, one hundred twenty million, two hundred twelve thousand, twenty-one".