My son could memorize songs and scripts faster than much older kids when he was four. I remember an older kid in his musical theater class telling me he must be "autistic or something" to be able to do that. When he was about seven he could listen to the news and remember all the main points and even paraphrase what he had heard so I knew it wasn't just memorization. When people would ask me if I had heard something in the news I could ask my son to tell us about it and he sounded so much smarter than I did that I let him answer. This stopped when he saw the reactions of people in our small town. As he got older he became more guarded about what he would say in front of people he didn't know very well.
He could remember enough about typical things someone he was imitating would say and use this to do really good impressions of them. Combined with his sense of humor he could do comical improve scenarios with his impressions. He has an extremely good memory for sounds and smells.
My mother had a really good memory for jeopardy type trivia. She read all the time. Her memory was good until she was in her 60's and had surgery. I am trying not to think about that right now.
