Of the 610,245 immigrants to the UK during the July to September 2009 period, 371,000 were students who can apply for a NI number and work part time legally, but cannot claim benefits.
That leaves 239,245 potential benefits claimants.
Of these 239,245, 112,000 were work permit holders and their dependents, all of who can work, apply for a NI No but who again cannot claim benefits.
That leaves 127,245. Of these 85,000 were UK residents, some of whom may or may not be perfectly entitled to claim benefits. Others due to the length of time spent outside the UK, will not be entitled to claim certain benefits. That leaves us with 42,245.
29,085 of these were from eastern European countries that require worker registration. As stated above, some of these are entitled under reciprocal EU arrangements to certain benefits.
Of the remaining 13,160, 5,055 were asylum seekers. The remainder would be Youth Mobility, Ancestry visa entrants and such, none of whom can claim benefits.