A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4820634 can be evenly divided by 1 2 3 6 7 9 13 14 18 21 26 27 39 42 54 63 78 81 91 109 117 126 162 182 189 218 234 243 273 327 351 378 486 546 567 654 702 763 819 981 1,053 1,134 1,417 1,526 1,638 1,701 1,962 2,106 2,289 2,457 2,834 2,943 3,159 3,402 4,251 4,578 4,914 5,886 6,318 6,867 7,371 8,502 8,829 9,919 12,753 13,734 14,742 17,658 19,838 20,601 22,113 25,506 26,487 29,757 38,259 41,202 44,226 52,974 59,514 61,803 76,518 89,271 114,777 123,606 178,542 185,409 229,554 267,813 344,331 370,818 535,626 688,662 803,439 1,606,878 2,410,317 and 4,820,634, with no remainder.
Since 4,820,634 cannot be divided by just 1 and 4,820,634, it is not a prime number.