Count by 639 (Skip Counting by 639s)

Count by 639

Here we will show you how to count by 639, discuss counting by 639 patterns, and tell you why knowing how to count by 639 matters. To start off, note that Count by 639 means counting in 639s, or count by six hundred thirty-nines, and it is also called skip counting by 639.

How to count by 639
Normally, we would count by 1 like this: 1, 2, 3, 4, etc., but when we count by 639, we count 639, 1278, 1917, 2556, and so on.

In other words, to count in intervals of 639 or skip counting by 639, we start with 639 and then add 639 to get the next number, and then continue adding 639 to the previous number to keep counting by 639, like this:

639
639 + 639 = 1278
1278 + 639 = 1917
1917 + 639 = 2556
2556 + 639 = 3195
...

You can of course skip count by 639 forever, so it is impossible to make a list of all numbers, but below is a Count by 639 Chart of the first 100 numbers to get you started.

Looking at the chart above, you will see that the first column has the first ten numbers you get when you skip count by 639, the second column has the next ten numbers you get when you skip count by 639, and so forth.

Count by 639 Patterns
We organized the Skip Counting by 639s Chart above in 10 rows and 10 columns so you can easily identify patterns.

Skip counting always creates patterns. Figuring out these patterns may help you if want to count by 639, but don't have the Counting by 639s Chart above. Obviously, one pattern with counting by 639s is that the number increases by 639.

Furthermore, if you look at each row above, each number in the row has the same last digit (ones place). That means that every tenth number has the same last digit.

If you look down the columns, you will see that the last digit (ones place) repeats itself in blocks of 10 over and over. The pattern of the last digit when you count by 639 goes 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 and 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 and so on for as long as you count by 639.

Why Count by 639?
We think that understanding and learning about skip counting by 639 is important, because it teaches you how the arithmetic operations fit together. Below are some examples of what we mean.

When you count by six hundred thirty-nine, you are also creating a list of multiples of 639 that you can use in math when you need the least common multiple. 639 times n equals the nth multiple or skip count of 639.

When you skip count by 639, you are also creating a list of numbers that 639 is divisible by. On top of that, skip counting by 639 is the same as making the 639 times table.

Skip Counting
Need to skip count by another number? Enter another number for us to skip count for you.

Count by 640
Here is the next number on our list that we used to skip count.