A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2970072 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 18 21 24 28 36 42 56 63 71 72 83 84 126 142 166 168 213 249 252 284 332 426 497 498 504 568 581 639 664 747 852 994 996 1,162 1,278 1,491 1,494 1,704 1,743 1,988 1,992 2,324 2,556 2,982 2,988 3,486 3,976 4,473 4,648 5,112 5,229 5,893 5,964 5,976 6,972 8,946 10,458 11,786 11,928 13,944 17,679 17,892 20,916 23,572 35,358 35,784 41,251 41,832 47,144 53,037 70,716 82,502 106,074 123,753 141,432 165,004 212,148 247,506 330,008 371,259 424,296 495,012 742,518 990,024 1,485,036 and 2,970,072, with no remainder.
Since 2,970,072 cannot be divided by just 1 and 2,970,072, it is not a prime number.