211220220121 has 2 divisors, whose sum is σ = 211220220122. Its totient is φ = 211220220120.

The previous prime is 211220220049. The next prime is 211220220137. The reversal of 211220220121 is 121022022112.

It is a happy number.

211220220121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (211220220137) can be obtained adding 211220220121 to its sum of digits (16).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147330074896 + 63890145225 = 383836^2 + 252765^2 .

It is a cyclic number.

It is not a de Polignac number, because 211220220121 - 2⁷ = 211220219993 is a prime.

It is a super-2 number, since 2×211220220121² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211220220095 and 211220220104.

It is not a weakly prime, because it can be changed into another prime (211220220181) 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, 105610110060 + 105610110061.

It is an arithmetic number, because the mean of its divisors is an integer number (105610110061).

Almost surely, 2^211220220121 is an apocalyptic number.

It is an amenable number.

211220220121 is a deficient number, since it is larger than the sum of its proper divisors (1).

211220220121 is an equidigital number, since it uses as much as digits as its factorization.

211220220121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 211220220121 its reverse (121022022112), we get a palindrome (332242242233).

The spelling of 211220220121 in words is "two hundred eleven billion, two hundred twenty million, two hundred twenty thousand, one hundred twenty-one".