As a typographical side note, the following mnemonic describes the difference between an orphan and a widow:
"An orphan starts alone, a widow ends alone."
- An orphan refers to a single word or line left at the bottom of a page, with the remainder of the paragraph appearing in the next column or following page;
- A widow refers to a single word or line that is forced to be separated from a paragraph that overflows into the next column or onto the following page;
(La)TeX refers to an orphan as being a "club" and provides an associated penalty for that - \clubpenalty
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There is no specific search that covers this type of query, unless it's tagged that way, since Stack Exchange's search capability provides no discernment between letters and numbers - they're both characters.
Your request seems to be more general that having a possible widow, as you want to join end-of-sentence numerals with the preceding word. My guess is that this would require a LuaLaTeX approach as a solution.
Alternatively, get in the habit of following Mr. Drofnats.