212220121 has 2 divisors, whose sum is σ = 212220122. Its totient is φ = 212220120.

The previous prime is 212220119. The next prime is 212220133. The reversal of 212220121 is 121022212.

It is a happy number.

212220121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 208398096 + 3822025 = 14436^2 + 1955^2 .

It is a cyclic number.

It is not a de Polignac number, because 212220121 - 2¹ = 212220119 is a prime.

Together with 212220119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (212220191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106110060 + 106110061.

It is an arithmetic number, because the mean of its divisors is an integer number (106110061).

Almost surely, 2^212220121 is an apocalyptic number.

It is an amenable number.

212220121 is a deficient number, since it is larger than the sum of its proper divisors (1).

212220121 is an equidigital number, since it uses as much as digits as its factorization.

212220121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 212220121 is about 14567.7768036169. The cubic root of 212220121 is about 596.4794958555.

Adding to 212220121 its reverse (121022212), we get a palindrome (333242333).

The spelling of 212220121 in words is "two hundred twelve million, two hundred twenty thousand, one hundred twenty-one".