Divisor 9203

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

The "Matthias Kuus Test" for Divisibility by 9203

To determine if any number is divisible by 9203, apply the "Matthias Kuus 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 202 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and add 2761 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 9203. That is, your original number is divisible by 9203 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 9203-times tables, it should be easy to visually see if Y is divisible by 9203. If the Y is still much larger than 9203, the above process can be repeated until it does reduce to within small multiples of 9203.

Easy!