What RGB profile do you use in the image or document? Use RGB.
Or is the document CMYK? Or the Colors CMYK? The picker picks always RGB numbers. Make sRGB as your working space in your case.
When I pdf it as an interactive pdf it changes to 234/33/45.
How are you measuring the values in the exported interactive PDF?
When you export to Interactive PDF all color is converted to profiled sRGB, so for the real color value to export unchanged the source profile would have to also be sRGB (Edit>Assign Profiles...>RGB Profile>Assign Profile)