A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 9257472 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 16 18 21 24 28 32 36 41 42 48 49 56 63 64 72 82 84 96 98 112 123 126 128 144 147 164 168 192 196 224 246 252 256 287 288 294 328 336 369 384 392 441 448 492 504 512 574 576 588 656 672 738 768 784 861 882 896 984 1,008 1,148 1,152 1,176 1,312 1,344 1,476 1,536 1,568 1,722 1,764 1,792 1,968 2,009 2,016 2,296 2,304 2,352 2,583 2,624 2,688 2,952 3,136 3,444 3,528 3,584 3,936 4,018 4,032 4,592 4,608 4,704 5,166 5,248 5,376 5,904 6,027 6,272 6,888 7,056 7,872 8,036 8,064 9,184 9,408 10,332 10,496 10,752 11,808 12,054 12,544 13,776 14,112 15,744 16,072 16,128 18,081 18,368 18,816 20,664 20,992 23,616 24,108 25,088 27,552 28,224 31,488 32,144 32,256 36,162 36,736 37,632 41,328 47,232 48,216 55,104 56,448 62,976 64,288 72,324 73,472 75,264 82,656 94,464 96,432 110,208 112,896 128,576 144,648 146,944 165,312 188,928 192,864 220,416 225,792 257,152 289,296 330,624 385,728 440,832 514,304 578,592 661,248 771,456 1,028,608 1,157,184 1,322,496 1,542,912 2,314,368 3,085,824 4,628,736 and 9,257,472, with no remainder.
Since 9,257,472 cannot be divided by just 1 and 9,257,472, it is not a prime number.