Pronouncing kanji numbers

Question

ホグワーツには一四二もの階段があった。
There were as many as 142 staircases at Hogwarts.

This is probably a daft question but I'd like to be sure. When you see a number written in kanji like 一四二 do you read it as ひゃくよんじゅうに or as separate numbers いち　よん　に? Does it make any difference if the text is written vertically?

Answer 1

In this context, 一四二 obviously means one-hundred-and-forty-two, so it's read ひゃくよんじゅうに. You can read it as いちよんに when it's a room number, zip code, etc. The kan-sūji style is much more preferred in vertical writing, but writing it horizontally won't change how to read it.

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