The Biggest Number in the Whole World

When a child is learning to count, they may ask, "What is the biggest number in the whole world?"

You can *tell them that if you told them a really big number, they could always add 1 to it and get a bigger number. You could go on like that forever, always adding to the previous number. This concept that numbers (and space) are endless is called infinity.  It is written as ∞

We can also discuss how to read and write extremely large numbers.

When we write numbers, they are separated into groups of 3 (counting from the right) and separated by commas.

Example: 307,756,123,904

From the right, the second group is thousand, the third is million, the next one is billion.

This number is three hundred seven billion, seven hundred fifty-six million, one hundred twenty-three thousand, nine hundred four.
For each group of 3 the designations (from the right) are:

• (None, just say that 3 digit number)
• Thousand: say the 3 digits normally, then add the word "thousand", not "thousands".
• Million
• Billion
• Trillion
• Quadrillion
• Quintillion
• Septillion
• Octillion
• And more, endlessly.