Harshad Years

Harshad number is an integer divisible by the sum of its digits.

Curiously enough, the years 2022-2025 are Harshad numbers. More than 2 consecutive Harshad years is so rare that it last happened 1000+ back for years 1014-1017. And will next happen after 1000+ years in 3030-3033.

The Puzzling Ramanujan’s Magic Square

As you maybe know, a magic square is a square divided into smaller squares each containing a number, such that the figures in each vertical, horizontal, and diagonal row add up to the same value.

In this particular magic square by Ramanujan, fields of the same color add up to 139. The first row – highlighted in the bottom-right magic square – shows his date of birth.