212001222221 has 2 divisors, whose sum is σ = 212001222222. Its totient is φ = 212001222220.

The previous prime is 212001222151. The next prime is 212001222259. The reversal of 212001222221 is 122222100212.

It is a happy number.

212001222221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145455280996 + 66545941225 = 381386^2 + 257965^2 .

It is a cyclic number.

It is not a de Polignac number, because 212001222221 - 2¹⁴ = 212001205837 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212001222221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212001224221) 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 as a sum of consecutive naturals, namely, 106000611110 + 106000611111.

It is an arithmetic number, because the mean of its divisors is an integer number (106000611111).

Almost surely, 2^212001222221 is an apocalyptic number.

It is an amenable number.

212001222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

212001222221 is an equidigital number, since it uses as much as digits as its factorization.

212001222221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 212001222221 its reverse (122222100212), we get a palindrome (334223322433).

It can be divided in two parts, 21200 and 1222221, that added together give a palindrome (1243421).

The spelling of 212001222221 in words is "two hundred twelve billion, one million, two hundred twenty-two thousand, two hundred twenty-one".