191

This number is a prime.

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191 is a palindromic Sophie Germain twin prime whose sum of digits (11) is also a palindromic Sophie Germain twin prime. Furthermore, the number created by eliminating the first and last digit is a perfect square (9). Note: It could also be said that the number of digits of 191 (3 in this case) is a palindromic Sophie Germain twin prime. [Trexaurius]