actually, its hard to tell you what is the exact figure..are you staying in a hotel?or relatives?what is your lifestyle?are u gonna go shopping?party?who will finance for food?are u gonna rent a car?a cheap meal for one person would cost you about 5-10 pounds, taxi is a bit expensive?which part of uk are u staying anyway..if its in london then its lil bit expensive..maybe if you can figure out how you gonna spend your 6 months here then i could estimate a figure..for sure u wont be bringing alot of money..u can widraw in atm anytime you wish..youre 5million is about 50,000 pounds..