12212012211221 has 4 divisors (see below), whose sum is σ = 12212260689132. Its totient is φ = 12211763733312.

The previous prime is 12212012211197. The next prime is 12212012211251. The reversal of 12212012211221 is 12211221021221.

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 3202349619121 + 9009662592100 = 1789511^2 + 3001610^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12212012211221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12212012211193 and 12212012211202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12212012211251) 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, 124165220 + ... + 124263533.

It is an arithmetic number, because the mean of its divisors is an integer number (3053065172283).

Almost surely, 2^{12212012211221} is an apocalyptic number.

It is an amenable number.

12212012211221 is a deficient number, since it is larger than the sum of its proper divisors (248477911).

12212012211221 is an equidigital number, since it uses as much as digits as its factorization.

12212012211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248477910.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 12212012211221 its reverse (12211221021221), we get a palindrome (24423233232442).

The spelling of 12212012211221 in words is "twelve trillion, two hundred twelve billion, twelve million, two hundred eleven thousand, two hundred twenty-one".