Compound numbers in Chinese are built on a 'tens + ones' frame: 二十 'twenty' + 九 'nine' → 二十九. Same pattern for 35 (三十五), 47 (四十七), etc. No connective word — just stack.
culture
On the lunar calendar, 大年二十九 (lit. 'big-year 29th') is the day before Lunar New Year's Eve in years where the 12th lunar month is 'short' (only 29 days) — important for prep: shopping, last-minute haircuts, sticking up couplets.
