If the entire world wanted to get bitcoin there would only be enough for .0028767 per person. Meaning the price would be astronomical. The only flaw in this theory is that chances are it wouldn't be every single person, nor would everyone pump every single penny in, so if we take a conservitive estimate of 10% of wealth into bitcoin, meaning we can move the decimal over to get .028767 bitcoin per person. But that still doesnt really answer the question, What will the price be? For this a different approach is needed. The new method is to work backwards and taking the global market cap of all registered businesses (64 trillion) and assuming 10% (6.4 trillion) we can divide that by 21 million bitcoins (maximum that will ever exist) and we then see a price of 304,761. Not too bad if you ask me.
Sources: http://data.worldbank.org/indicator/CM.MKT.LCAP.CD
https://coinmarketcap.com/