How many millennia separate our time and era?

The era of ancient civilizations, that is, Egyptian and Sumerian, dates back to the Bronze Age, which began in the middle of 4 thousand BC. Thus, we can say that there is a time difference of 5.5 thousand years between us and them. These ancient civilizations were essentially pioneers, they were the first to master science, construction, trade, etc. Thanks to them, we received a lot of knowledge that we use until now.