Divisor 8951

Prime Number:
Yes!
Divisibility test:
The "Jon-Paul Query Test"
Test Discovered by:
Matt Parker
Date:
11/11/2024

The "Jon-Paul Query Test" for Divisibility by 8951

To determine if any number is divisible by 8951, apply the "Jon-Paul Query Test":

  1. If your number ("X") has 9 digits or more, separate the last (smallest) 8 digits from the rest. This makes two smaller numbers, call them Left and Right (note: don't add in trailing zeros to L). If there are fewer than 9 digits, L = 0 and therefore R = X.
  2. Multiply L by 572 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 895 times the digit you just crossed off. Call this final result "Y".
  4. Y will be much smaller than X, but we have preserved divisibility by 8951. That is, your original number is divisible by 8951 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 8951-times tables, it should be easy to visually see if Y is divisible by 8951. If the Y is still much larger than 8951, the above process can be repeated until it does reduce to within small multiples of 8951.

Easy!