A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2320344 can be evenly divided by 1 2 3 4 6 8 9 12 13 18 24 26 36 37 39 52 67 72 74 78 104 111 117 134 148 156 201 222 234 268 296 312 333 402 444 468 481 536 603 666 804 871 888 936 962 1,206 1,332 1,443 1,608 1,742 1,924 2,412 2,479 2,613 2,664 2,886 3,484 3,848 4,329 4,824 4,958 5,226 5,772 6,968 7,437 7,839 8,658 9,916 10,452 11,544 14,874 15,678 17,316 19,832 20,904 22,311 29,748 31,356 32,227 34,632 44,622 59,496 62,712 64,454 89,244 96,681 128,908 178,488 193,362 257,816 290,043 386,724 580,086 773,448 1,160,172 and 2,320,344, with no remainder.
Since 2,320,344 cannot be divided by just 1 and 2,320,344, it is not a prime number.