An $\textit{emirp}$ is an integer that, when its digits are written in reverse order, is a prime number. For example, 73 is an emirp because 37 is prime. What is the smallest two-digit prime number that is NOT an emirp?
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<|im_start|>user
An $\textit{emirp}$ is an integer that, when its digits are written in reverse order, is a prime number. For example, 73 is an emirp because 37 is prime. What is the smallest two-digit prime number that is NOT an emirp?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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An $\textit{emirp}$ is an integer that, when its digits are written in reverse order, is a prime number. For example, 73 is an emirp because 37 is prime. What is the smallest two-digit prime number that is NOT an emirp?
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