Quote: I get that one, it's a billion and that's actually pretty obvious
No it isn't! Obvious, I mean.
What Europe has (and the system British English used to have, even if the name is not used) but what Americans completely missed out on, is the milliard - a thousand million. The US, and modern British, billion. The short billion.
When you have a milliard you have the long scale of a billion being a million million.
Quote:
English
milliardFrom French milliard.
Numeral
milliard (plural milliards)
(now rare) 10^9, a thousand times a million. (Now generally replaced by the short scale billion.) [from 18th c.]
The name 'milliard' is not used in English, but the words 'a thousand million' are used in British English to make it clear, because a billion is something different to many people - a million million.
But most western European languages still use the milliard

eg Icelandic,
hundrað (2), þúsund (3), milljón (6), milljarður (9), billjón (12), then combine or, if you want, billjarður (15), trilljón(18), trilljarður (21). Then it just gets silly, but if you ever feel the need - kvaðrilljón (24), kvaðrilljarður (27) kvintilljón (30)
It is precise, a new name for every thousand times increase.
In between, use "a hundred million", or if you don't want to use a milliard, as in English, "a thousand million".

(It is labelled as 'mixed' in Canada because French Canadians use the French milliard system, so the long billion = million million).
There is a difference between what is used in internally, and what is used when dealing with American and British systems internationally - and the result is a lot of confusion, especially by those who don't realise there is another system. (Not to insult Americans in particular, but the education system there does tend to leave people with less awareness than some countries, that some other places do things differently - I think you will agree on that one?) !
Anything bigger than a hundred million is
1 impossible to comprehend anyway, so a few zeros make little difference to any visualisation
2 best given in scientific notation if you want to be clear
edit - some repetition of what Bob has said.