Divisor 17417

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

The "Tim Göller Test" for Divisibility by 17417

To determine if any number is divisible by 17417, apply the "Tim Göller Test":

  1. If your number ("X") has 8 digits or more, separate the last (smallest) 7 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 8 digits, L = 0 and therefore R = X.
  2. Multiply L by 2642 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 5225 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 17417. That is, your original number is divisible by 17417 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 17417-times tables, it should be easy to visually see if Y is divisible by 17417. If the Y is still much larger than 17417, the above process can be repeated until it does reduce to within small multiples of 17417.

Easy!