# Number Pie Chart

What should be the missing number?

• For the number theorists out there, I'd say this puzzle is rather (ROT13) anepvffvfgvp :P – Mr Pie Sep 29 '18 at 12:15

$13139$

Because,

Power $4$ the digits. Summing them will get you to the next number.

$4338$ -> $4^4 + 3^4 + 3^4 + 8^4$ -> $4514$.
$4514$ -> $4^4 + 5^4 + 1^4 + 4^4$ -> $1138$.
...

And yes,

It makes a cycle, :)