28 (number) facts for kids

Twenty-eight is a cool number that you might find interesting! It's a whole number that comes right after twenty-seven and just before twenty-nine. Twenty-eight is an even number, which means you can divide it by two without having anything left over.

Understanding 28's Properties

What Divides 28?

When we say a number is "divisible by" another, it means you can divide it evenly. For 28, you can divide it perfectly by several numbers. These numbers are called its divisors or factors. The factors of 28 are:

• 1
• 2
• 4
• 7
• 14
• 28

If you add up all these factors (except 28 itself), you get 1 + 2 + 4 + 7 + 14 = 28. This special property makes 28 a very unique number!

Prime Factors of 28

Every whole number greater than 1 can be broken down into prime factors. Prime numbers are numbers that can only be divided by 1 and themselves (like 2, 3, 5, 7, etc.). For 28, its prime factors are 2, 2, and 7. This means you can multiply them together to get 28 (2 × 2 × 7 = 28).

28 as a Perfect Number

Twenty-eight is known as a perfect number. A perfect number is a positive integer that is equal to the sum of its positive divisors, not including the number itself. As we saw, the divisors of 28 (excluding 28) are 1, 2, 4, 7, and 14. When you add them up (1 + 2 + 4 + 7 + 14), the sum is exactly 28! The perfect number that came before 28 was six.

Images for kids

• 

  The number 28 can be shown as 28 balls arranged in a triangular shape with 7 layers.

See also

In Spanish: Veintiocho para niños