I love dates that are mathematically interesting. Today is either 9/16/2023 or 16/9/2023, depending on where you live in the world. Which means that the following are all true:
The month is the square of three (the last digit of the year).
The day of the month is the square of four (the sum of the first three digits of the year).
If you add the month and the day together, you get the square of five (the sum of the last three digits of the year).
If you add up the month and the digits of the year, you get 9 + 2 + 0 + 2 + 3 = 16, which is the day of the month.