Check what are the decimals for your currency in TCURX table. This is the main reason for your issue.
Just put value as 2 in TCURX table for HUF currency. This will resolve your issue. No formula is required.
How to put value:
SPRO-->SAP Netweaver-->general Settings-->Currencies-->Set Decimal Places for Currencies-->Put value as 2 for HUF-->Save it
Come back to query and run it..