Divisor 5081

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

The "Connor Mcharg Test" for Divisibility by 5081

To determine if any number is divisible by 5081, apply the "Connor Mcharg Test":

  1. If your number ("X") has 5 digits or more, separate the last (smallest) 4 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 5 digits, L = 0 and therefore R = X.
  2. Multiply L by 162 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 508 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 5081. That is, your original number is divisible by 5081 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 5081-times tables, it should be easy to visually see if Y is divisible by 5081. If the Y is still much larger than 5081, the above process can be repeated until it does reduce to within small multiples of 5081.

Easy!