Update README.md

README.md

@@ -519,7 +519,7 @@ I'll keep updating for full summary and better solutions. Stay tuned for updates
 829 | [Consecutive Numbers Sum](https://leetcode.com/problems/consecutive-numbers-sum/) | [C++](./C++/consecutive-numbers-sum.cpp) [Python](./Python/consecutive-numbers-sum.py) | _O(sqrt(n))_ | _O(1)_ | Medium |||
 836 | [Rectangle Overlap](https://leetcode.com/problems/rectangle-overlap/) | [C++](./C++/rectangle-overlap.cpp) [Python](./Python/rectangle-overlap.py) | _O(1)_ | _O(1)_ | Easy |||
 858 | [Mirror Reflection](https://leetcode.com/problems/mirror-reflection/) | [C++](./C++/mirror-reflection.cpp) [Python](./Python/mirror-reflection.py) | _O(1)_ | _O(1)_ | Medium |||
-867 | [Prime Palindrome](https://leetcode.com/problems/prime-palindrome/) | [C++](./C++/prime-palindrome.cpp) [Python](./Python/prime-palindrome.py) | _O(1)_ | _O(1)_ | Medium |||
+867 | [Prime Palindrome](https://leetcode.com/problems/prime-palindrome/) | [C++](./C++/prime-palindrome.cpp) [Python](./Python/prime-palindrome.py) | _O(n^(1/2) * (logn + n^(1/2)))_ | _O(logn)_ | Medium |||
 883 | [Projection Area of 3D Shapes](https://leetcode.com/problems/projection-area-of-3d-shapes/) | [C++](./C++/projection-area-of-3d-shapes.cpp) [Python](./Python/projection-area-of-3d-shapes.py) | _O(n^2)_ | _O(1)_ | Easy |||
 887 | [Super Egg Drop](https://leetcode.com/problems/super-egg-drop/) | [C++](./C++/super-egg-drop.cpp) [Python](./Python/super-egg-drop.py) | _O(klogn)_ | _O(1)_ | Hard |||
 891 | [Sum of Subsequence Widths](https://leetcode.com/problems/sum-of-subsequence-widths/) | [C++](./C++/sum-of-subsequence-widths.cpp) [Python](./Python/sum-of-subsequence-widths.py) | _O(n)_ | _O(1)_ | Hard |||