A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2744000 can be evenly divided by 1 2 4 5 7 8 10 14 16 20 25 28 32 35 40 49 50 56 64 70 80 98 100 112 125 140 160 175 196 200 224 245 250 280 320 343 350 392 400 448 490 500 560 686 700 784 800 875 980 1,000 1,120 1,225 1,372 1,400 1,568 1,600 1,715 1,750 1,960 2,000 2,240 2,450 2,744 2,800 3,136 3,430 3,500 3,920 4,000 4,900 5,488 5,600 6,125 6,860 7,000 7,840 8,000 8,575 9,800 10,976 11,200 12,250 13,720 14,000 15,680 17,150 19,600 21,952 24,500 27,440 28,000 34,300 39,200 42,875 49,000 54,880 56,000 68,600 78,400 85,750 98,000 109,760 137,200 171,500 196,000 274,400 343,000 392,000 548,800 686,000 1,372,000 and 2,744,000, with no remainder.
Since 2,744,000 cannot be divided by just 1 and 2,744,000, it is not a prime number.