I - IICIDHOAVIC (Laureate and draped bust of Louis The Pious on the right, the third I inclined).
NVMVIIONVMIIM (circular legend around a cross surrounded by a circle made up of dots).
Photo of the copy preserved at the Bibliothèque Nationale de France (public domain), link to the page of their website showing the photo of the coin: https://gallica.bnf.fr/ark:/12148/btv1b104139674.r=louis%20le%20pieux?rk=2467823;2.
The letters following the number (1 A, 1 B..) classify the coins according to their quality of representation.
Obverse legend copied: DN HLVDOVVICVS IMP AVG
Reverse legend copied: NVMVS DIVINVM
The letters M on the reverse look like N, I have chosen to note them as being letters M because their location seems to follow the copied legend in order: NVMVS DIVINVM.
|N°||G||F||XF 40||AU 58||MS 63||MS 65|
Seems never to have gone on sale.