This is probably caused by some places using long scales and others short scales:
"For powers of ten less than 9 (one, ten, hundred, thousand and million) the short and long scales are identical, but for larger powers of ten, the two systems differ in confusing ways. For identical names, the long scale grows by multiples of one million (106), whereas the short scale grows by multiples of one thousand (103). For example, the short scale billion is one thousand million (109), whereas in the long scale, billion is one million million (1012). The long scale system includes additional names for interleaved values, typically replacing the word ending "-ion" by "-iard". "
How do I know this? I live in a country that uses Long Scales. Or this is a problem with the particular way the japanese write their numbers.