exigible
demandable
exigir
to demand
+
-ible
able to be
Exigible means demandable and can be thought of as exigir0 (to demand0) + -ible1 (able to be1), so it's something that is able to be demanded.
adjective
- demandableThat can be demanded or requiredEl pago es exigible al final del mes. // The payment is demandable at the end of the month.