From TFA: But wait, there’s more! As you probably know, people in some countries write their dates out with the day before the month. In that case, 27 September, 2025 would be 27/09/2025. If we run the same trick as before, 27/09/2025 turns into 27,092,025. Lo and behold, that is the square of 5,205—5205 times 5205 is 27,092,025.