A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 8089536 can be evenly divided by 1 2 3 4 6 7 8 12 13 14 16 21 24 26 28 32 39 42 48 52 56 64 78 84 91 96 104 112 156 168 182 192 208 224 273 312 336 364 416 448 463 546 624 672 728 832 926 1,092 1,248 1,344 1,389 1,456 1,852 2,184 2,496 2,778 2,912 3,241 3,704 4,368 5,556 5,824 6,019 6,482 7,408 8,736 9,723 11,112 12,038 12,964 14,816 17,472 18,057 19,446 22,224 24,076 25,928 29,632 36,114 38,892 42,133 44,448 48,152 51,856 72,228 77,784 84,266 88,896 96,304 103,712 126,399 144,456 155,568 168,532 192,608 207,424 252,798 288,912 311,136 337,064 385,216 505,596 577,824 622,272 674,128 1,011,192 1,155,648 1,348,256 2,022,384 2,696,512 4,044,768 and 8,089,536, with no remainder.
Since 8,089,536 cannot be divided by just 1 and 8,089,536, it is not a prime number.