A possible solution is Math::Currency:

use Math::Currency qw(Money $LC_MONETARY);
Math::Currency->format( $LC_MONETARY->{EUR} );
Math::Currency->format('MON_THOUSANDS_SEP', '\'');
print Math::Currency::Money(12345.67);
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this code prints €12'345,67. Your question was thoroughly answered here: Making money look nice.

Ciao, Valerio