211121100221 has 2 divisors, whose sum is σ = 211121100222. Its totient is φ = 211121100220.

The previous prime is 211121100209. The next prime is 211121100259. The reversal of 211121100221 is 122001121112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 140914648996 + 70206451225 = 375386^2 + 264965^2 .

It is a cyclic number.

It is not a de Polignac number, because 211121100221 - 2¹⁰ = 211121099197 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211121100196 and 211121100205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211121106221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105560550110 + 105560550111.

It is an arithmetic number, because the mean of its divisors is an integer number (105560550111).

Almost surely, 2^211121100221 is an apocalyptic number.

It is an amenable number.

211121100221 is a deficient number, since it is larger than the sum of its proper divisors (1).

211121100221 is an equidigital number, since it uses as much as digits as its factorization.

211121100221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 211121100221 its reverse (122001121112), we get a palindrome (333122221333).

The spelling of 211121100221 in words is "two hundred eleven billion, one hundred twenty-one million, one hundred thousand, two hundred twenty-one".