As noted in another answer, this is currently called by GameScience a d20 0-9 Twice. Historically, this is what d20's looked like before the invention of the proper d10. (Note that Platonic solids are only possible with 4, 6, 8, 12, or 20 sides, and these are the entirety of what early dice sets contained.) Indeed, common usage would be to color half the faces in a distinct color to indicate values above 10. Thus, the one die could be used as a d10, d20, and d%. Some old-school gamers still prefer them for perceived elegance and efficiency in this way.
Here are some quotes from the 1E AD&D DMG (1979) on usage of such dice. Note that the modern d10/d% is not included in the illustration, and the d20 (0-9) is referred to as the standard d20. From the Dice section (p. 9-10):
If a d20 is used either 1-20 (assuming the use of a standard d20 which
is numbered 0-9 twice without coloring one set of faces to indicate
that those faces have 10 added to the number appearing) or 1-40
(assuming that one set of faces is colored) can be gotten by adding 0
if 1 or 2 is rolled on the d4 and 10 or 20 (depending on die type) if
a 3 or 4 is rolled...
The d20 is used often, both as d10 and d20. The bell-shaped
probability curves typically range from 2-20 to 5-50, i.e., 2, 3, 4 or
5d20 added together. Also common is the reading as above with one
decimal place added to the result to get 20-200,30-300, etc. In the
latter case, a roll of 3 on one die and 0 (read as 10) totals 13, plus
one place, or 130.
Non-platonic solid-shaped dice are available in some places. The most
common of these is a ten-sided die numbered 0-9. As with the d20, this
can be used for many purposes, even replacing the d20 if a second die
is used in conjunction to get 5% interval curves (1-20). Also, the die
can give 0-9 linear curve random numbers, as the d20 can.
You might also want to watch this informative video by Jon Peterson on the history, manufacture, and how to identify different brands of dice from the 1970's (noting that everyone made d20's with a single digit per face until TSR started doing differently in 1980). Jon says that in the early 1970's some people called these decimal dice or deci-dice (at about the 3:40 mark of the video).