MLA style spells out the names of centuries in prose and in titles of English-language works, even when the title page uses a numeral:
Queen Victoria ruled England for most of the nineteenth century.
Music of the Twentieth Century
We make an exception and retain the numeral if it precedes an abbreviation in a title:
The Ekopolitan Project: Migrant Histories and Family Genealogies from 19th and 20th c. Lagos
For the titles of foreign-language works, we follow the source. Although the th in English-language ordinal numbers is set on the baseline, the equivalent in French—the abbreviations -e or -ième following numerals—is set superscript:
Manet et le monde du XIXe siècle
Published 3 April 2018