Divisor 6959

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

The "Magnus Torset Test" for Divisibility by 6959

To determine if any number is divisible by 6959, apply the "Magnus Torset 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 83 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and add 696 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 6959. That is, your original number is divisible by 6959 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 6959-times tables, it should be easy to visually see if Y is divisible by 6959. If the Y is still much larger than 6959, the above process can be repeated until it does reduce to within small multiples of 6959.

Easy!