Yes, 13 is a whole number. Whole numbers are a set of numbers that include all the natural numbers (1, 2, 3, …) and zero (0). Since 13 is a positive integer without any fractional or decimal part, it is classified as a whole number.
Whole numbers are used in various mathematical operations and are fundamental in counting and ordering. They are distinct from integers, which include negative numbers, and from real numbers, which include fractions and decimals.