A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 7440615 can be evenly divided by 1 3 5 7 9 13 15 21 23 35 39 45 63 65 69 79 91 105 115 117 161 195 207 237 273 299 315 345 395 455 483 553 585 711 805 819 897 1,027 1,035 1,185 1,365 1,449 1,495 1,659 1,817 2,093 2,415 2,691 2,765 3,081 3,555 4,095 4,485 4,977 5,135 5,451 6,279 7,189 7,245 8,295 9,085 9,243 10,465 12,719 13,455 15,405 16,353 18,837 21,567 23,621 24,885 27,255 31,395 35,945 38,157 46,215 63,595 64,701 70,863 81,765 94,185 107,835 114,471 118,105 165,347 190,785 212,589 323,505 354,315 496,041 572,355 826,735 1,062,945 1,488,123 2,480,205 and 7,440,615, with no remainder.
Since 7,440,615 cannot be divided by just 1 and 7,440,615, it is not a prime number.