Dear Straight Dope:

How much is a gazillion, exactly?

SDStaff Dex replies:

Million, billion, trillion, quadrillion, quintillion, sextillion, septillion, octillion, novillion, decillion . . . lessee, a decillion is:

1,000,000,000,000,000,000,000,000,000,000,000

. . . so there ain’t no gazillion, it’s right up there with zillion, bijillion, and uncountabillion . . . a made-up term.

Just so you know, here’s the list of “named illions”:

Billion has 9 zeros

Trillion has 12 zeros

Quadrillion has 15 zeros

Quintillion has 18 zeros

Sextillion has 21 zeros

Septillion has 24 zeros

Octillion has 27 zeros

Nonillion has 30 zeros

Decillion has 33 zeros

Undecillion has 36 zeros

Duodecillion has 39 zeros

Tredecillion has 42 zeros

Quattuordecillion has 45 zeros

Quindecillion has 48 zeros

Sexdecillion has 51 zeros

Septendecillion has 54 zeros

Octodecillion has 57 zeros

Novemdecillion has 60 zeros

Vigintillion has 63 zeros

Googol has 100 zeros.

Centillion has 303 zeros (except in Britain, where it has 600 zeros)

Googolplex has a googol of zeros

(Please also see my discussion of “googol” at http://www.straightdope.com/mailbag/mgoogol.html.)

You may remember that one of the Teeming Millions once chastised Cecil for referring to “googols of snowflakes,” pointing out that 1 googol was greater than the number of protons, electrons, and neutrons in the known universe. Sure, pal. Let’s see you count ’em.

One last thing. The number list above refers to American number-naming practice. As long as we’re quoting other Web know-it-alls (hey, why should Cecil have to do all the work?), here’s what Doctor Math has to say on the topic:

*“In the English speaking world, at least, there’s already disagreement about what the word “billion” means. In the United States, it means 10 ^{9} in Great Britain, it means 10^{12}. The Brits add 6 zeroes per step up, and we add 3. So a British “trillion” is 10^{18}. In a sense, the British system makes more sense — billion, trillion, quadrillion, etc., indicate 2, 3, and 4 from the roots of the names. If you think of them as meaning 2, 3, and 4 groups of 6 zeroes, everything makes good sense — and it makes no sense in the U.S. system.”*

Our number billion, I might add, is known in Britain as a “milliard.” The Germans, who evidently follow British practice, take it a step farther and use *die Billiarde*, which is the equivalent of quadrillion in the U.S.

OK. So, can anybody lend me two bucks for lunch?

Send questions to Cecil via cecil@straightdope.com.

STAFF REPORTS ARE WRITTEN BY THE STRAIGHT DOPE SCIENCE ADVISORY BOARD, CECIL'S ONLINE AUXILIARY. THOUGH THE SDSAB DOES ITS BEST, THESE COLUMNS ARE EDITED BY ED ZOTTI, NOT CECIL, SO ACCURACYWISE YOU'D BETTER KEEP YOUR FINGERS CROSSED.