Divisor 5077

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

The "McKayla Test" for Divisibility by 5077

To determine if any number is divisible by 5077, apply the "McKayla 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 154 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 1523 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 5077. That is, your original number is divisible by 5077 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 5077-times tables, it should be easy to visually see if Y is divisible by 5077. If the Y is still much larger than 5077, the above process can be repeated until it does reduce to within small multiples of 5077.

Easy!