Q: Is 561,561 a Prime Number?
A: No, 561,561 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 561561 can be evenly divided by 1 3 7 11 13 17 21 33 39 51 77 91 119 121 143 187 221 231 273 357 363 429 561 663 847 1,001 1,309 1,547 1,573 2,057 2,431 2,541 3,003 3,927 4,641 4,719 6,171 7,293 11,011 14,399 17,017 26,741 33,033 43,197 51,051 80,223 187,187 and 561,561, with no remainder.
Since 561,561 cannot be divided by just 1 and 561,561, it is not a prime number.