211021221211217 has 2 divisors, whose sum is σ = 211021221211218. Its totient is φ = 211021221211216.

The previous prime is 211021221211121. The next prime is 211021221211223. The reversal of 211021221211217 is 712112122120112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122766488640016 + 88254732571201 = 11080004^2 + 9394399^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211021221211217 is a prime.

It is not a weakly prime, because it can be changed into another prime (211021221211817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105510610605608 + 105510610605609.

It is an arithmetic number, because the mean of its divisors is an integer number (105510610605609).

Almost surely, 2^{211021221211217} is an apocalyptic number.

It is an amenable number.

211021221211217 is a deficient number, since it is larger than the sum of its proper divisors (1).

211021221211217 is an equidigital number, since it uses as much as digits as its factorization.

211021221211217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 26.

Adding to 211021221211217 its reverse (712112122120112), we get a palindrome (923133343331329).

The spelling of 211021221211217 in words is "two hundred eleven trillion, twenty-one billion, two hundred twenty-one million, two hundred eleven thousand, two hundred seventeen".