The Community Edition allows you to have a maximum of 400 visitors per day, only.
To accomodate such traffic you would require a Basic Edition for at least 50 concurrent users (=4000 visitors per day). Depending on your business return the initial investment may fit your needs.
Please see more at http://www.outsystems.com/pricing/
You can better understand the differences between the several Outsystems Plataform editions in the Agile Platform Editions web page. For a more detailed description on this, you can see the Agile Platform Editions document.
As Pedro said, you can easily simmulate the pricing on different configurations the OutSystems Agile Platform on the Agile Platform Pricing simulator.
I hope this information is of any help.