Divisor 12041

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

The "Sascha Tölkes Test" for Divisibility by 12041

To determine if any number is divisible by 12041, apply the "Sascha Tölkes 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 505 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 1204 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 12041. That is, your original number is divisible by 12041 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 12041-times tables, it should be easy to visually see if Y is divisible by 12041. If the Y is still much larger than 12041, the above process can be repeated until it does reduce to within small multiples of 12041.

Easy!