A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3599730 can be evenly divided by 1 2 3 5 6 9 10 15 18 23 30 37 45 46 47 69 74 90 94 111 115 138 141 185 207 222 230 235 282 333 345 370 414 423 470 555 666 690 705 846 851 1,035 1,081 1,110 1,410 1,665 1,702 1,739 2,070 2,115 2,162 2,553 3,243 3,330 3,478 4,230 4,255 5,106 5,217 5,405 6,486 7,659 8,510 8,695 9,729 10,434 10,810 12,765 15,318 15,651 16,215 17,390 19,458 25,530 26,085 31,302 32,430 38,295 39,997 48,645 52,170 76,590 78,255 79,994 97,290 119,991 156,510 199,985 239,982 359,973 399,970 599,955 719,946 1,199,910 1,799,865 and 3,599,730, with no remainder.
Since 3,599,730 cannot be divided by just 1 and 3,599,730, it is not a prime number.