it is indeed the Antonov AN225, one of a kind flying, formerly part of the Russian space program, it ws intended to carry Buran on its back, (hence the blister fairings), derived from the Antonov AN124, by changing the tail to a H tail as opposed to conventional tail, extended span, and lengthening of the fuselage. it was resurected into life because Air Foyle / Antonov OKB who ran the AN124 were getting calls for transportation of loads that were too big for the 124.