Here is XLSX file with some boolean columns.
MS Office 2007 Excel show it as TRUE/FALSE.
Libre Office 5.2.7.2 Calc show it all as 0 ("=FALSE()" on edit).
Really in sheet1.xml you can see
<c r="P3" s="2" t="b"><v>true</v></c>
<c r="Q3" s="2" t="b"><v>false</v></c>