A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 9192120 can be evenly divided by 1 2 3 4 5 6 7 8 10 12 14 15 20 21 24 28 30 31 35 40 42 56 60 62 70 84 93 105 120 124 140 155 168 186 210 217 248 280 310 353 372 420 434 465 620 651 706 744 840 868 930 1,059 1,085 1,240 1,302 1,412 1,736 1,765 1,860 2,118 2,170 2,471 2,604 2,824 3,255 3,530 3,720 4,236 4,340 4,942 5,208 5,295 6,510 7,060 7,413 8,472 8,680 9,884 10,590 10,943 12,355 13,020 14,120 14,826 19,768 21,180 21,886 24,710 26,040 29,652 32,829 37,065 42,360 43,772 49,420 54,715 59,304 65,658 74,130 76,601 87,544 98,840 109,430 131,316 148,260 153,202 164,145 218,860 229,803 262,632 296,520 306,404 328,290 383,005 437,720 459,606 612,808 656,580 766,010 919,212 1,149,015 1,313,160 1,532,020 1,838,424 2,298,030 3,064,040 4,596,060 and 9,192,120, with no remainder.
Since 9,192,120 cannot be divided by just 1 and 9,192,120, it is not a prime number.