廿 (w)

(niàn) twenty (20), in a limited number of set expressions; also written using banker's character 念

廿八躔 (w)

(niànbāchán) the twenty-eight constellations; also written 二十八宿[er4 shi2 ba1 xiu4]

廿四史 (w)

(niànsìshǐ) twenty four dynastic histories (or 25 or 26 in modern editions); same as 二十四史