Whenever you see a big number ending in zeros, it's very probable that the number has been rounded. It could be on the basis that the receiver either doesn't need to know the exact value, (it's not important) or the informant doesn't know what the actual number is.
In the following example, a football attendance, let's say, has been given to varying levels of accuracy, said to be rounding to a specified number of significant figures.
76 537 = 80 000 (to 1 s.f.)
= 77 000 (to 2 s.f.)
= 76 500 (to 3 s.f.)

The number of British troop deaths, at the time of writing, has reached 446. No zeros there and understandably so. We care what the actual number is and the relative low size makes it still possible to individualise each member of the set.
In contrast, I have heard many times, even opponents of the war in Iraq, refer to the 100, 000 Iraqi civilian deaths there have been as a consequence of the illegal war. The magnitude of this number seems to be undisputed but do you see the use of the zeros. Is it because we don't know the actual truth or simply we don't care? I honestly don't know but there's good news for if you visit the Iraq Body Count website one can access a far more accurate figure.
The concept of big numbers is a difficult one for young children to grasp. If you counted a million pounds, one pound every second, it would take over 12 days and nights to do it. It's a really humongous number. Ask the Great Train Robbers of 1963 who hadn't planned into their schedule the time involved to count their booty! The relative size of a million, billion and trillion are beautifully demonstrated by this film called, 'What does a trillion dollars loOK like?'
Think about it. It would need 44 000 articulated trucks to take 1 000 000 000 000 real dollars to the bank. The truth is that it's not and never will be real. I doubt if such an amount has ever been printed in the history of the world. Capitalism knows no limit and my fear is that many people don't realise the immensity of such illusory 'monopoly' numbers, like the UK National Debt
Journalists know that 1 000 000 people killed is a statistic whereas one person's plight is a story.
So History teachers, how about this way of getting over how many Jews were killed in the holocaust. 6 000 000 is the statistic that everyone knows, lots of zeros there, mind, remember our two rules?
I toOK a Year 7 class into our Drama hall and by lying head to toe, we estimated that we could fill the hall, sardine-like by 25 x 20 x 12 (= 6 000) bodies. The bowl volume of Wembley stadium is 1.1 million cubic metres which is conveniently about 1 000 times the size of our hall,... trust me I'm a Maths teacher!
Now what this means is that if you filled Wembley stadium, sardine-wise, with bodies to the top, that's how many Jews were killed in the extermination camps. The slightly smaller Millenium stadium in Cardiff should be big enough to carry the slightly less important
2 - 3 000 000 Soviet POWs
1.8 - 2 000 000 Ethnic Poles
220 000 - 1 500 000 Romani (interesting range!)
200 000 - 250 000 Disabled
90 000 Freemasons, Homosexuals, Jehovah's Witnesses

"What's that Danny! - there's a puppy in the playground?
Have you been listening to a damn thing I've been saying, boy?
Ok, chairs under, off you go."