12012021222221 has 4 divisors (see below), whose sum is σ = 12012097351452. Its totient is φ = 12011945092992.

The previous prime is 12012021222199. The next prime is 12012021222241. The reversal of 12012021222221 is 12222212021021.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7048950660196 + 4963070562025 = 2654986^2 + 2227795^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12012021222221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12012021222193 and 12012021222202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12012021222241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37827446 + ... + 38143671.

It is an arithmetic number, because the mean of its divisors is an integer number (3003024337863).

Almost surely, 2^{12012021222221} is an apocalyptic number.

It is an amenable number.

12012021222221 is a deficient number, since it is larger than the sum of its proper divisors (76129231).

12012021222221 is an equidigital number, since it uses as much as digits as its factorization.

12012021222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76129230.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 12012021222221 its reverse (12222212021021), we get a palindrome (24234233243242).

The spelling of 12012021222221 in words is "twelve trillion, twelve billion, twenty-one million, two hundred twenty-two thousand, two hundred twenty-one".