A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1384500 can be evenly divided by 1 2 3 4 5 6 10 12 13 15 20 25 26 30 39 50 52 60 65 71 75 78 100 125 130 142 150 156 195 213 250 260 284 300 325 355 375 390 426 500 650 710 750 780 852 923 975 1,065 1,300 1,420 1,500 1,625 1,775 1,846 1,950 2,130 2,769 3,250 3,550 3,692 3,900 4,260 4,615 4,875 5,325 5,538 6,500 7,100 8,875 9,230 9,750 10,650 11,076 13,845 17,750 18,460 19,500 21,300 23,075 26,625 27,690 35,500 46,150 53,250 55,380 69,225 92,300 106,500 115,375 138,450 230,750 276,900 346,125 461,500 692,250 and 1,384,500, with no remainder.
Since 1,384,500 cannot be divided by just 1 and 1,384,500, it is not a prime number.