1,000,000 is million to round look at hundred thousand place or 100,000 see number before million (after comma)
if it is greater than or equal to 5, add 1 to current value of million and say all after is 0 if less than 5 then leave million value as is and make after 0
135,458,267 hundred thousand value is 4 4<5 135,000,000
