10M, ten thousand
10MM, ten million
10MMM, ten billion
here in sec. 3: https://www.druide.com/fr/enquetes/abréviation-de-million-et...
Still I suppose it's better than sussing out whether someone is British and using "long" billions.
(in most of the world, "billion" = 10 to the 9th power; in older British usage still sometime seen, "billion" = 10 to the 12th power, and 10^9 is "thousand million")
Once you understand this system you might also understand why the long system makes more sense.
1000 = Mille M
1000 000 = Million MM
1000 000 000 = Milliard MM M
1000 000 000 000 = Billion MM MM
1000 000 000 000 000 = Billiard MM MM M
in the short system the billion (nine zeros) has nothing to do with two. while in the long system it represents double as many zeros as the million. a trillion has three times the Zeros. -ard suffix? add 3 zerosBritain does not use "long" billions. Not since the 1970s or so. Now days, billion always means 1000 million.
From the Guardian style guide:
"million - in copy use m for sums of money, units or inanimate objects: £10m, 45m tonnes of coal, 30m doses of vaccine; but million for people or animals: 1 million people, 23 million rabbits, etc; use m in headlines"
The plural part of your definition here is not really relevant.. i.e. 10M = ten thousand, 10MM = ten million, 1M = 1 thousand (not 1 million, singular)
Most people colloquially seem to use k for 'thousand' and most people would probably intuit M as 'million', but I think people still go with MM for avoidance of doubt.