[sam_bristow]

2025 had a bunch of bits of fun mathematical trivia:

45² = 45 x 45 = 2025

Also,

9² x 5² = 2025

40² + 20² + 5² = 2025

My favourite?

1³+2³+3³+4³+5³+6³+7³+8³+9³ = 2025

[thomaswc]

Ha! I really should have known that last one, given that I once wrote a paper about the sum of cubes. https://dl.acm.org/doi/abs/10.5555/1378446.1378486