Congratulations to the Kaprekar Number President-elect of the USA. Last time we had a Kaprekar President of the USA, it was William Henry Harrison, number 9. I’m not into magic numbers. I just looked up something interesting about the #45 and found this. Short tenure in office for WHH though. Kaprekar Number: Consider an n-digit number k. Square it and add the right n digits to the left n or n-1 digits. If the resultant sum is k, then k is called a Kaprekar number. For example, 9 is a Kaprekar number since 9^2=81 8+1=9, and 297 is a Kaprekar number since 297^2=88209 88+209=297. The first few are 1, 9, 45, 55, 99, 297, 703, … (OEIS A006886).

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