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