How do you write 4 8 million?
I can't tell if you are asking for 48 million or 4.8 million, so
I will answer for both.
48 million in numerical form, it is 48,000,000
(a number followed by 6 digits is 'millions')
4.8 million in numerical form is 4,800,000 (4 million 8 hundred
thousand)