You don't. There is no such number as 'zillion'
Zillion is not a real word.
How do write 666 in standard form?
It is already in standard form.
That is the standard form!
You write 6.11 in standard form as 6.11 × 100
Zillion is not a real word.
a zillion is not a real number so it's impossible
There is no such thing as the number "zillion".
A zillion is not a real number: it is a word used to mean a very very large number. There is, therefore no numerical form.
How do write 666 in standard form?
It is already in standard form.
That is the standard form!
That IS the standard form.
That is the standard form.
There is no such thing as the number "zillion". It is used only in slang term, as meaning "many". There is no definite number for zillion, because technically there isn't a 'zillion'.
You write 20.7 in standard form as: 2.07 × 101
You write 6.11 in standard form as 6.11 × 100