The number system of Ouxu is modeled after Lojban's system, except that the number words are ordinary roots. Here are the words for the numbers from zero to nine, plus the decimal point and the negative sign. Note that the vowels systematically run i e a o u, from higher to lower in pitch.

A number is a compound root. Simply write down a number as usual, such as -12,345.6. That is a correct Ouxu number in the form of a compound root whose pronunciation you can read off of the above table: isieeapaciutohohuulicihape-. As a root, of course you have to inflect it to use it in a sentence.

Ciu- is for numeric commas only. Commas are optional, but if used they should be three digits apart, at the thousands, the millions, and so on, just as in American English.

For clarity, numbers should be written as digits rather than spelled out.

Pa 2so iftupe.
Belief 2+attribute lake+exist.
There are two lakes.

4lo sugki.5a 2a ohe.
4+of to-the-power+.5+same 2+same realis.
The square root of four is two.

The international standard SI prefixes for numbers from 10^-15 to 10¹⁵ have been borrowed into Ouxu as roots.

2kika-
2+kika-
two billion (American)

kika2-
kika+2-
a billion and two (American)