When I was in my twenties, some friends who were in their late thirties casually commented that it often took them a bit to remember how old they were (like “How old am I now? Oh yeah, I’m 36, I think”).
I was pretty incredulous at the time, but now that I’ve aged, I often find it takes me a couple seconds to recall my exact age. You younger kids will no doubt think that I’m full of s@#t, but maybe some older redditors can confirm this.