A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4062048 can be evenly divided by 1 2 3 4 6 8 12 16 17 19 24 32 34 38 48 51 57 68 76 96 102 114 131 136 152 204 228 262 272 304 323 393 408 456 524 544 608 646 786 816 912 969 1,048 1,292 1,572 1,632 1,824 1,938 2,096 2,227 2,489 2,584 3,144 3,876 4,192 4,454 4,978 5,168 6,288 6,681 7,467 7,752 8,908 9,956 10,336 12,576 13,362 14,934 15,504 17,816 19,912 26,724 29,868 31,008 35,632 39,824 42,313 53,448 59,736 71,264 79,648 84,626 106,896 119,472 126,939 169,252 213,792 238,944 253,878 338,504 507,756 677,008 1,015,512 1,354,016 2,031,024 and 4,062,048, with no remainder.
Since 4,062,048 cannot be divided by just 1 and 4,062,048, it is not a prime number.