One way is to test all the prime numbers equal or less than Sqrt[251]. These are: {2,3,5,7,11,13}.
We can eliminate 2, 3, and 5 because the number isn't odd, it's digits don't sum to a multiple of 3, and the last digit isn't a 5 or a 0.
For 7, note that 252 = 7*36, so 7 cannot divide 251 because that would imply 7 divides 1.
For 11, note that 253 = 11*23, so 11 cannot divide 251 because that would imply 11 divides 2.
For 13, note that 13*19 = 247, so 13 cannot divide 251 because that would imply 13 divides 4.
Hence, 251 is prime
It is a prime number, and therefore not a composite number.251 is prime.
None. 251 is a prime number.
Just 1 and 251 because it is a prime number.
251
251
It is a prime number, and therefore not a composite number.251 is prime.
None. 251 is a prime number.
251 is a prime number; its factors are 1 and itself.
Just 1 and 251 because it is a prime number.
Only itself and one because 251 is a prime number
251
The prime factorization of 3,514 is: 2 × 7 × 251
251
no,753 is not prime ,it can be divided by 251 and 3.that makes it composite.
Only by 1 and itself since it is a prime number.
Pointless, 251 is prime.
NO!!! If you add the adigtis 2259 = 2 + 2 + 5 + 9 = 18 + 1 + 8 = 9 This means that the number will divide, has a factor of '9'. 2259/9= 251 So 2259 is a composite number, not a prime number.