2000€ enough for 7 weeks in Japan?

Question:

I'm going to Japan this July and August for 7 weeks. We'll mostly be using couchsurfing and spend few nights in hostels. We're gonna buy one 2 week JR pass and one 1 week pass (already paid, means not included in those 2000€), the rest of the time we'll be traveling with buses and local trains. We plan to stay around 18 days in Tokyo and 1 week somewhere on the beach and eat cheap food. I calculated that 7 weeks in Japan with 2000€ means 40€ per day. Is that enough considering lodging will be free most of the time?
We will be traveling between Tokyo and Hiroshima with trips north to Shirakawa go and east of Tokyo to Nikko.

Answer:

It is not enough for one person for 7 weeks. If you were going to Laos then yes that would be fine but you are going to Japan - back to the drawing board i say:)