How would you read the number 40,500'? forty thousand and five hundred? forty thousand five handred?

When there are zeroes in a number, is "and" compulsive? How many zeroes in a number entails "and"? Thank you very much.
I teach my students to say 'and' only after the word 'hundred', although it also appears in many speakers for the sake of rhythm if there are a number of consecutive zeros-- the number of zeros per se is not important, however:

40,500 = forty thousand, five hundred
40,501 = forty thousand, five hundred and one
40,551 = forty thousand, five hundred and fifty-one
40,001 = forty thousand (and) one
40,001 = forty thousand (and) one

In English (not American) this "and" is not optional. An English person would never say "forty thousand one." In fact it "sounds American".
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I was taught in school that it is a rule for Americans to read 45,671 as "forty-five thousand, six hundred seventy-one" whereas for British people as " forty-five thousand, six hundred and seventy-one" ['and' comes after 'hundred'].

As for your question (40,500), I have googled as follows to know how people read it actually.

  • EDU/GOV(American) domains ..."forty thousand five hundred" 56 : "forty thousand and five hundred" 18

  • UK (British) domain .................. "forty thousand five hundred" 21 : "forty thousand and five hundred" 55.

  • The balance is somehow different between AmE and BrE, but there seems in both countries some people who like to insert 'and' before 'hundred'.
Thank you all for yor help. Speaking of "and" coming after "hundred", I remember my grammar book as saying that "and" comes after "hundred" wherever "hundred" appears in a number, for example, the number 234,506,789 should be read "two hundred and thirty-four million, five hundred and six, seven hundred and eighty-nine". Is it correct? Thank you very much.
That's the way I teach it, but there are obviously variations abroad.
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The number 234,506,789 should be read "two hundred and thirty-four million, five hundred and six thousand, seven hundred and eighty-nine".

I think that is the way British people speak. Americans would read mostly as "two hundred thirty-four million, five hundred [ou] six thousand, seven hundred [and] eighty-nine". Here [ou] and [and] are optional.