There is no easy test. You need to divide the number by all the primes up to the square root of the number, so if you want to know if 56789 is prime, you need to divide by all the prime numbers up to 239. If you go through all the primes up to the square root and don't get an even number as the result of the division then the number is prime. (Incidentally, the factors of 56789 are 109 and 521.)
Divide it with primes less than half of the number.
on my test it said is 1.68 a prime number i sed yes but it was no :(
Their are many ways one that some times works is test those answers if prime are Mersenne primes. Or you could google"Is (put the questionable number here)prime?"
59
Easiest way to answer this question yourself is can this number be divided by 2 or 3 and not have a decimal or any "leftover" numbers? 999997 / 2 = 499998.5 = Nope 999997 / 3 = 333332.33 = Nope Answer: Yes, 999997 is a prime number. No, the above is not a legitimate prime test. 999997 is actually 757 * 1321 and is not prime. There is no easy prime test you can do in your head that I know of.
To determine if 2558 is a prime number, you would typically test divisibility by numbers up to the square root of 2558. The square root of 2558 is approximately 50.58. Therefore, you would test divisibility by prime numbers up to 51. The greatest prime number less than or equal to 51 is 47, so you would test divisibility by 47 to determine if 2558 is a prime number.
You only need to test numbers up to the last prime number equal to or less than the square root of a number when testing whether it is prime. The square root of 854 is between 29 and 30, so you would test up to the prime number 29.
Divide it with primes less than half of the number.
on my test it said is 1.68 a prime number i sed yes but it was no :(
Their are many ways one that some times works is test those answers if prime are Mersenne primes. Or you could google"Is (put the questionable number here)prime?"
59
53
For goodness sake! This will be on a test one day and you will not know it! But, the answer is no, it is prime
A prime number is any number that only has one and itself as factors. Therefore, to tell if a number is prime simply find it's factors. If it has more than two factors than it is not a prime number.
A prime number is a positive integer with two factors: one and the number itself. If you test the numbers up to the square root and your number is not divisible by any of them, it's prime.
A prime number is a positive integer with two factors: one and the number itself. If you test the numbers up to the square root and your number is not divisible by any of them, it's prime.
A prime number is a positive integer with two factors: one and the number itself. If you test the numbers up to the square root and your number is not divisible by any of them, it's prime.