"Unfathomable Numbers: Beyond Human Imagination"

There are numbers so large that they cannot be imagined or expressed, and some infinities are larger than others, according to mathematicians. The largest number is infinite, but there are hierarchies of ever-bigger numbers beyond trillions, such as quadrillions, quintillions and sextillions. A centillion has 303 zeroes in the US version, and a googol is a one followed by 100 zeroes. A googol plex is 10 to the power of a googol, and there are numbers smaller than a googol plex that cannot be reduced to a simpler notation or a single word.