Millions
First consider a million:

One million is a thousand thousands.2﻿
One million is a 1 with six zeros after it, denoted by 1,000,000.
One million seconds is about 11 and a half days.
One million pennies stacked on top of each other would make a tower nearly a mile high.3﻿
If you earn \$45,000 a year, it would take 22 years to amass a fortune of 1 million dollars.
One million ants would weigh a little over 6 pounds.
One million dollars divided evenly among the U.S. population would mean everyone in the United States would receive about one-third of one cent.

Billions
Next up is one billion:

One billion is a thousand millions.
One billion is a 1 with nine zeros after it, denoted by 1,000,000,000.
One billion seconds is about 32 years.4
One billion pennies stacked on top of each other would make a tower almost 870 miles high.3﻿
If you earn \$45,000 a year, it would take 22,000 years to amass a fortune of one billion dollars.
One billion ants would weight over 3 tons—a little less than the weight of an elephant.
One billion dollars divided equally among the U.S. population would mean that everyone in the United States would receive about \$3.33.3﻿

Trillions
After this is a trillion:

One trillion is a thousand billions, or equivalently a million millions.
It is a 1 with 12 zeros after it, denoted by 1,000,000,000,000.
One trillion seconds is 32,000 years.5﻿
One trillion pennies stacked on top of each other would make a tower about 870,000 miles high—the same distance obtained by going to the moon, back to Earth, then to the moon again.3﻿
One trillion ants would weigh over 3,000 tons.
One trillion dollars divided evenly among the U.S. population would mean that everyone in the United States would receive a little over \$3,000.3﻿