SOLUTION: Sir I Need some help in how to determine whether the given number is prime or not for the large numbers. for ex.119547120987

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Question 375731: Sir I Need some help in how to determine whether the given number is prime or not for the large numbers. for ex.119547120987
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Numbers that end in 7 are sometimes divisible by 7 and 9.
So check using 7 and 9.
119547120987=3%2A3%2A7%2A7%2A191%2A479%2A2963
There are other guidelines too.
Numbers that end in 2,4,6,8,0 are divisible by 2.
Numbers that end in 3 are sometimes divisible by 3.
Numbers that end in 0 or 5 are divisible by 5.
Numbers that end in 6 are sometimes divisble by 2 and 3.
Numbers that end in 9 are sometimes divisible by 3.