The factors of 28 are 1, 2, 4, 7, 14 and 28. To get the factors, the number 28 must be divided by whole numbers starting from 1, and the quotient must also be a whole number. If this is the case, the quotient and the divisor are considered factors for the number in question.
The number 28 may be presented as a product of 1 and 28, which are two of the factors. It may also be calculated as a product of the following number combinations: 2 and 14, and 4 and 7.
A convenient way to determine the factors of any number is to start with the number 1. The most basic pair of factors of any number is the number 1 and the number itself, since any number multiplied by one is equal to itself. After this, divide the number by two and check if the quotient is a whole number. If it is, include this pair of divisor and quotient as factors of the number. Continue with number 3 and succeeding numbers until the number pairs become as close as possible. All of the whole number pairs generated using this method are the factors of the given number.