Trying to ask `"Which number president is Donald Trump"` and then `"Donald
trump is the 45th President of the U.S."`

I think the first could be `どちらの大統領はXですか？` but it sounds too simplistic?
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2017-07-13T22:47:17.600
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2017-07-14T01:30:20.810
2017-07-14T01:30:20.810
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question
grammar
How do I ask and say "X is the nth president"