221221120217 has 2 divisors, whose sum is σ = 221221120218. Its totient is φ = 221221120216.

The previous prime is 221221120199. The next prime is 221221120229. The reversal of 221221120217 is 712021122122.

221221120217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111842756041 + 109378364176 = 334429^2 + 330724^2 .

It is a cyclic number.

It is not a de Polignac number, because 221221120217 - 2⁸ = 221221119961 is a prime.

It is a super-2 number, since 2×221221120217² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221221120192 and 221221120201.

It is not a weakly prime, because it can be changed into another prime (221221120247) 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, 110610560108 + 110610560109.

It is an arithmetic number, because the mean of its divisors is an integer number (110610560109).

Almost surely, 2^221221120217 is an apocalyptic number.

It is an amenable number.

221221120217 is a deficient number, since it is larger than the sum of its proper divisors (1).

221221120217 is an equidigital number, since it uses as much as digits as its factorization.

221221120217 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 23.

Adding to 221221120217 its reverse (712021122122), we get a palindrome (933242242339).

The spelling of 221221120217 in words is "two hundred twenty-one billion, two hundred twenty-one million, one hundred twenty thousand, two hundred seventeen".