Find the smallest prime palindrome greater than or equal to N.
Recall that anumber is prime if it's only divisors are 1 and itself, and it is greater than 1.
For example, 2,3,5,7,11 and 13 areprimes.
Recall that a number is a palindrome if it reads the same from left to right as it does from right to left.
For example, 12321 is a palindrome.
Example 1:
Input: 6
Output: 7
Example 2:
Input: 8
Output: 11
Example 3:
Input: 13
Output: 101
Note:
- 1 <= N <= 10^8
- The answer is guaranteed to exist and be less than 2 * 10^8.
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