221211010217 has 2 divisors, whose sum is σ = 221211010218. Its totient is φ = 221211010216.

The previous prime is 221211010211. The next prime is 221211010249. The reversal of 221211010217 is 712010112122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 185579162521 + 35631847696 = 430789^2 + 188764^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221211010217 is a prime.

It is a super-2 number, since 2×221211010217² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221211010211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110605505108 + 110605505109.

It is an arithmetic number, because the mean of its divisors is an integer number (110605505109).

Almost surely, 2^221211010217 is an apocalyptic number.

It is an amenable number.

221211010217 is a deficient number, since it is larger than the sum of its proper divisors (1).

221211010217 is an equidigital number, since it uses as much as digits as its factorization.

221211010217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 221211010217 its reverse (712010112122), we get a palindrome (933221122339).

The spelling of 221211010217 in words is "two hundred twenty-one billion, two hundred eleven million, ten thousand, two hundred seventeen".