Multiplication characteristics of nine

The sum of each number is a multiple of 9.

According to the inquiry of education and training, the multiple characteristic of 9 is that the sum of the numbers on each digit is a multiple of 9, and the multiple of 9 is 9, 18, 27, 36, 45, 54, 63, 72, 8 1, 90, 99, 108, and so on.

An integer can be divisible by another integer, which is a multiple of another integer. Similarly, the quotient obtained by dividing one number by another. For example, a/b=c, that is, A is a multiple of B, and a number has countless multiples, which means that the set of multiples of a number is infinite. It should be noted that a number cannot be called a multiple alone, only that a number is a multiple of another number.