I'm speculating when I say that I think all these USES are using the word number where the sense of "thing" applies: a hot thing, rolling a thing, doing a thing.

我推想，在这些用法里，凡是出现number的地方都可以用thing来替代而不改变原意，比如：ahotthing,rolling a thing,doing a thing。

youdao

For the present is the only thing of which a man can be deprived, if it is true that this is the only thing which he has, and that a man cannot lose a thing if he has it not.

如果这是真的，即一个人只拥有现在，那么一个人就不可能丧失一件他并不拥有的东西。

youdao

For the present is the only thing of which a man can be deprived, if it is true that this is the only thing which he has, and that a man cannot lose a thing if he has it not.

如果这是真的，即一个人只拥有现在，那么一个人就不可能丧失一件他并不拥有的东西。

youdao