Q: Is 1,666,665 a Prime Number?
A: No, 1,666,665 is not a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1666665 can be evenly divided by 1 3 5 7 9 11 13 15 21 33 35 37 39 45 55 63 65 77 91 99 105 111 117 143 165 185 195 231 259 273 315 333 385 407 429 455 481 495 555 585 693 715 777 819 1,001 1,155 1,221 1,287 1,295 1,365 1,443 1,665 2,035 2,145 2,331 2,405 2,849 3,003 3,367 3,465 3,663 3,885 4,095 4,329 5,005 5,291 6,105 6,435 7,215 8,547 9,009 10,101 11,655 14,245 15,015 15,873 16,835 18,315 21,645 25,641 26,455 30,303 37,037 42,735 45,045 47,619 50,505 79,365 111,111 128,205 151,515 185,185 238,095 333,333 555,555 and 1,666,665, with no remainder.
Since 1,666,665 cannot be divided by just 1 and 1,666,665, it is not a prime number.