Pi Day (March 14) is a day of global mathematical celebration, but it’s not the only numerically significant calendar date. It’s far from the rarest, either. In fact, today marks a special occasion ...

Pi Day (3/14) often comes with sweet treats; Square Root Day (4/4/16 or 5/5/25, for example) has a certain numerical rhyme. But the particular string of numbers in today’s date may be especially ...

September 16, 2025, is the only date that fits the definition this century. Here’s the specific math to add it all up: 3 multiplied by itself is 9, 4 squared is 16, and 5 squared is 2025. On top of ...

Once a century, a very special day comes along. That day is today — 9/16/25. Pi Day (3/14) often comes with sweet treats; Square Root Day (4/4/16 or 5/5/25, for example) has a certain numerical rhyme.