Roman <codec>
from 1…18,446,744,073,709,551,615
Encoding successful The roman numeral equivalent of `10,000,000,000` is `X̅̅̅`.
What is the bar above the numeral? The large numeral contains a
vinculum. Each bar represents the numeral multiplied by 1,000. If you do not see a line above the numeral, then your browser's monospace font does not support this diacritical mark.
Here are some others for you to try...