Divisor 11731

Prime Number:
Yes!
Divisibility test:
The "Mik Scheper Test"
Test Discovered by:
Matt Parker
Date:
11/11/2024

The "Mik Scheper Test" for Divisibility by 11731

To determine if any number is divisible by 11731, apply the "Mik Scheper Test":

  1. If your number ("X") has 10 digits or more, separate the last (smallest) 9 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 10 digits, L = 0 and therefore R = X.
  2. Multiply L by 2636 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 1173 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 11731. That is, your original number is divisible by 11731 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 11731-times tables, it should be easy to visually see if Y is divisible by 11731. If the Y is still much larger than 11731, the above process can be repeated until it does reduce to within small multiples of 11731.

Easy!