211121221111217 has 2 divisors, whose sum is σ = 211121221111218. Its totient is φ = 211121221111216.

The previous prime is 211121221111193. The next prime is 211121221111223. The reversal of 211121221111217 is 712111122121112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 140943054339136 + 70178166772081 = 11871944^2 + 8377241^2 .

It is a cyclic number.

It is not a de Polignac number, because 211121221111217 - 2¹⁰ = 211121221110193 is a prime.

It is not a weakly prime, because it can be changed into another prime (211121221114217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105560610555608 + 105560610555609.

It is an arithmetic number, because the mean of its divisors is an integer number (105560610555609).

Almost surely, 2^{211121221111217} is an apocalyptic number.

It is an amenable number.

211121221111217 is a deficient number, since it is larger than the sum of its proper divisors (1).

211121221111217 is an equidigital number, since it uses as much as digits as its factorization.

211121221111217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 224, while the sum is 26.

Adding to 211121221111217 its reverse (712111122121112), we get a palindrome (923232343232329).

The spelling of 211121221111217 in words is "two hundred eleven trillion, one hundred twenty-one billion, two hundred twenty-one million, one hundred eleven thousand, two hundred seventeen".