Actually, the 0.7182818284590452353602874713527th day of February is the 11th.
So 2019/2.7182818284590452353602874713527 is February 11, 2019, at about 02:41:07.399 in the morning.
Another important value derived from e is 0.63212055882855767840447622983854 = (e-1)/e = "Tau". This represents what's known as the "Exponential Decay Constant" in physics and the "Time Constant" in electrical engineering.
Happy eDay!

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The mere fact that science may not yet adequately explain an object, event, or experience does not mean the immediate explanation should automatically default to a conspiratorial, extraterrestrial, paranormal, or supernatural cause.