A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3445400 can be evenly divided by 1 2 4 5 7 8 10 14 20 23 25 28 35 40 46 50 56 70 92 100 107 115 140 161 175 184 200 214 230 280 322 350 428 460 535 575 644 700 749 805 856 920 1,070 1,150 1,288 1,400 1,498 1,610 2,140 2,300 2,461 2,675 2,996 3,220 3,745 4,025 4,280 4,600 4,922 5,350 5,992 6,440 7,490 8,050 9,844 10,700 12,305 14,980 16,100 17,227 18,725 19,688 21,400 24,610 29,960 32,200 34,454 37,450 49,220 61,525 68,908 74,900 86,135 98,440 123,050 137,816 149,800 172,270 246,100 344,540 430,675 492,200 689,080 861,350 1,722,700 and 3,445,400, with no remainder.
Since 3,445,400 cannot be divided by just 1 and 3,445,400, it is not a prime number.