641 imperial pints in US customary cups
Result
The conversion result is: 641 imperial pints is equivalent to 1539.61780449722 US customary cups.[1]
Conversion formula
How to convert 641 imperial pints to US customary cups?
We know (by definition) that: 1 imperialpint ≈ 2.40189985100971 uscup.
We can set up a proportion to solve for the number of US customary cups.
1 imperialpint / 641 imperialpint ≈ 2.40189985100971 uscup / x uscup
Now, we cross multiply to solve for our unknown x:
x uscup ≈ (641 imperialpint / 1 imperialpint) * 2.40189985100971 uscup → x uscup ≈ 1539.6178044972241 uscup
Conclusion:
641 imperialpint ≈ 1539.6178044972241 uscup

Conversion in the opposite direction
The inverse of the conversion factor is that 1 US customary cup is equal to 0.000649511844484391 times 641 imperial pints.
It can also be expressed as: 641 imperial pints is equal to 1 / 0.000649511844484391 US customary cups.
Approximation
An approximate numerical result would be: six hundred and forty-one imperial pints is about one thousand, five hundred and thirty-nine point six one US customary cups, or alternatively, a US customary cup is about zero times six hundred and forty-one imperial pints.
Footnotes
[1] The precision is 15 significant digits (fourteen digits to the right of the decimal point).
Results may contain small errors due to the use of floating point arithmetic.