Puzzle #67: My prime

From New Scientist #3290, 11th July 2020 [link] [link]

I am thinking of a two-digit prime number. The special thing about my prime, though, is that if I square its two digits, the difference between these square numbers is also prime.

As it happens, I haven’t given you enough information to identify my number. But whatever my number is, you can be certain that its two digits have a particular relationship to each other. What is that relationship?

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