Page 158 - Easy Japanese - Learn to Speak Japanese Quickly! (TUTTLE)

10,000 ichi-man
20,000 ni-man
30,000 san-man
40,000 yon-man
50,000 go-man
60,000 roku-man
70,000 nana-man

80,000 hachi-man
90,000 kyū-man
0 rei/ zero
how many 100’s?
how many 1000’s?
how many 10,000’s?

nan-byaku
nan-zen
nan-man

GRAMMAR NOTE Numbers Above 100

In English numbers are grouped by thousands, millions, billions, and thus you

see a comma after every three places to the left of the decimal—1,000,000,000.
In Japanese, numbers are counted in groups of four places and traditionally a
comma was inserted every four places—10,0000,0000. Ten thousand in Japanese
has a special name man, and succeeding groups of four places, have the names -
oku “one hundred million”, and -chō “one trillion”.
Note that you need to say ichi only for the last place in each four-place group.
So, 10, 100 and 1000 do not require ichi.

1 ichi 10,000 ichi-man
10 jū 100,000 jū-man

100 hyaku 1,000,000 hyaku-man
1,000 sen 10,000,000 sen-man

¥1111,1111 is sen hyaku jū ichi man sen hyaku jū ichi en.

Also note the following sound changes.
For 100s (hyaku) h → b 300 sanbyaku

?00 nanbyaku (how many hundreds?)