A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 7337850 can be evenly divided by 1 2 3 5 6 10 13 15 25 26 30 39 50 53 65 71 75 78 106 130 142 150 159 195 213 265 318 325 355 390 426 530 650 689 710 795 923 975 1,065 1,325 1,378 1,590 1,775 1,846 1,950 2,067 2,130 2,650 2,769 3,445 3,550 3,763 3,975 4,134 4,615 5,325 5,538 6,890 7,526 7,950 9,230 10,335 10,650 11,289 13,845 17,225 18,815 20,670 22,578 23,075 27,690 34,450 37,630 46,150 48,919 51,675 56,445 69,225 94,075 97,838 103,350 112,890 138,450 146,757 188,150 244,595 282,225 293,514 489,190 564,450 733,785 1,222,975 1,467,570 2,445,950 3,668,925 and 7,337,850, with no remainder.
Since 7,337,850 cannot be divided by just 1 and 7,337,850, it is not a prime number.