A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 9251400 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 17 20 24 25 30 34 40 50 51 60 68 75 85 100 102 120 136 150 170 200 204 255 300 340 408 425 510 600 680 850 907 1,020 1,275 1,700 1,814 2,040 2,550 2,721 3,400 3,628 4,535 5,100 5,442 7,256 9,070 10,200 10,884 13,605 15,419 18,140 21,768 22,675 27,210 30,838 36,280 45,350 46,257 54,420 61,676 68,025 77,095 90,700 92,514 108,840 123,352 136,050 154,190 181,400 185,028 231,285 272,100 308,380 370,056 385,475 462,570 544,200 616,760 770,950 925,140 1,156,425 1,541,900 1,850,280 2,312,850 3,083,800 4,625,700 and 9,251,400, with no remainder.
Since 9,251,400 cannot be divided by just 1 and 9,251,400, it is not a prime number.