Q: Is 21,531,825 a Composite Number?

Why is 21,531,825 a composite number?

A composite number is a number that can be divided evenly by more numbers than 1 and itself. It is the opposite of a prime number.

The number 21,531,825 can be evenly divided by 1 3 5 7 9 15 21 25 27 31 35 45 49 63 75 81 93 105 135 147 155 175 189 217 225 245 279 315 343 405 441 465 525 567 651 675 735 775 837 945 1,029 1,085 1,225 1,323 1,395 1,519 1,575 1,715 1,953 2,025 2,205 2,325 2,511 2,835 3,087 3,255 3,675 3,969 4,185 4,557 4,725 5,145 5,425 5,859 6,615 6,975 7,595 8,575 9,261 9,765 10,633 11,025 12,555 13,671 14,175 15,435 16,275 17,577 19,845 20,925 22,785 25,725 27,783 29,295 31,899 33,075 37,975 41,013 46,305 48,825 53,165 62,775 68,355 77,175 87,885 95,697 99,225 113,925 123,039 138,915 146,475 159,495 205,065 231,525 265,825 287,091 341,775 439,425 478,485 615,195 694,575 797,475 861,273 1,025,325 1,435,455 2,392,425 3,075,975 4,306,365 7,177,275 and 21,531,825, with no remainder.

Since 21,531,825 cannot be divided by just 1 and 21,531,825, it is a composite number.

More Examples

• All positive natural numbers are either a prime number or a composite number (except the number 1, which is neither).