What is the product of the two integer values for $x$ for which $|x^2 - 16|$ is a prime number?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
What is the product of the two integer values for $x$ for which $|x^2 - 16|$ is a prime number?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
-9
What is the product of the two integer values for $x$ for which $|x^2 - 16|$ is a prime number?
train