2025 in Math
Note: You will have to scroll horizontally to view the math on mobile
Let’s celebrate the new year by investigating some of the interesting mathematical properties of the number 2025. Many of these facts were sourced from this Reddit thread. Thank you to everyone that shared their insight.
2025 is a Square Year
This is a personal favorite. It’s short and easy to remember.
2025 is a perfect square, and it may be the only square year for many of us.
This may hold special significance for those born in 1980, as they will turn 45 this year.
Squared Sum and Sum of Cubes
2025 can be expressed as a square of the sum of [1, 9], and also the sum of the cubes of [1, 9]:
This is known as Nichomachus’ Theorem
Let’s see if we can prove it.
Sum of Odd Numbers
2025 can be expressed as the sum of all odd numbers in the range [1, 90],
This is a property that applies to any square number, let’s prove it
2025 is a Pythagorean Triple
2025 is part of a Pythagorean Triple, meaning that it is the hypotenuse of a right-angled triangle with natural length adjacent and opposite sides