211221211222117 has 2 divisors, whose sum is σ = 211221211222118. Its totient is φ = 211221211222116.

The previous prime is 211221211222061. The next prime is 211221211222141. The reversal of 211221211222117 is 711222112122112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 201849475975876 + 9371735246241 = 14207374^2 + 3061329^2 .

It is a cyclic number.

It is not a de Polignac number, because 211221211222117 - 2²⁷ = 211221077004389 is a prime.

It is a super-2 number, since 2×211221211222117² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211221211228117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610605611058 + 105610605611059.

It is an arithmetic number, because the mean of its divisors is an integer number (105610605611059).

Almost surely, 2^{211221211222117} is an apocalyptic number.

It is an amenable number.

211221211222117 is a deficient number, since it is larger than the sum of its proper divisors (1).

211221211222117 is an equidigital number, since it uses as much as digits as its factorization.

211221211222117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 896, while the sum is 28.

Adding to 211221211222117 its reverse (711222112122112), we get a palindrome (922443323344229).

The spelling of 211221211222117 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, one hundred seventeen".