What number is the only whole number that is not a natural number?

The only whole number that isn't a natural number is 0

Answer: 0

Step-by-step explanation: Natural numbers are the set of counting numbers that start at 0 an go on indefinitely.

Example ⇒ {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ... }

When we include 0 in the set of natural numbers, we get the new set of numbers which is called the set of whole numbers.

Example ⇒ {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ... }

All of the natural numbers are contained within the set of whole numbers.