211111221000221 has 2 divisors, whose sum is σ = 211111221000222. Its totient is φ = 211111221000220.

The previous prime is 211111221000187. The next prime is 211111221000233. The reversal of 211111221000221 is 122000122111112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130122272623225 + 80988948376996 = 11407115^2 + 8999386^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211111221000221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 211111221000221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211111221008221) 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, 105555610500110 + 105555610500111.

It is an arithmetic number, because the mean of its divisors is an integer number (105555610500111).

Almost surely, 2^{211111221000221} is an apocalyptic number.

It is an amenable number.

211111221000221 is a deficient number, since it is larger than the sum of its proper divisors (1).

211111221000221 is an equidigital number, since it uses as much as digits as its factorization.

211111221000221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 211111221000221 its reverse (122000122111112), we get a palindrome (333111343111333).

The spelling of 211111221000221 in words is "two hundred eleven trillion, one hundred eleven billion, two hundred twenty-one million, two hundred twenty-one", and thus it is an aban number.