the queen is the most followed royal on twitter with 970,000 followers .
next most popular is prince charles , then spain 's king felipe .
prince harry and the duke and duchess of cambridge also popular .
spoof @queen_uk tops the lot with 1.25 m - more than the real queen .
top celebrities include katy perry , justin bieber and taylor swift .
uk 's top politician is david cameron and australia 's is tony abbott .
us president obama is the world 's most followed politician .