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No! Not by a long shot. With larger numbers, you cannot tell whether an odd number is prime or composite just by the last digits. All prime numbers greater than 7 must end in one or these: 1, 3, 7 or 9. But not all numbers ending with 1, 3, 7 or 9 are prime.
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Well for example 207 is divisible by 3 so the answer is no (207 is 69 times three). The simple test (ie to check for 3 as divisor or also called a factor) is to add all the individual numbers up (here it totals 9) and then if that number is divisible by three then you don't have a Prime number. So 27 is also not a prime - it divides by three. (quick check again the total of the numbers is 9 ie divisible by three) and another example 57 can be divided by 3 to give 19 and the quick check is 5 and 7 totals 12 which is then divisible by three.
ps don't forget you need to check for all the other numbers also! ie like 4, 5, 7, 9, 11, 13 ... etc
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What different numbers are there in maths?
There is no end to the numbers of maths and there are many classifications of numbers, like primes, fractions, even, odd, positive, negative and others.
How many of the digits in the prime numbers end in 13579?
As there are infinitely many primes (as Euclid proved circa 300 BC) and not all of them are (or can be) known, it is impossible to answer this question.
What is the greatest difference between 2 consecutive prime numbers?
There is no limit: gaps between successive primes can be arbitrarily large. As of 2014, the largest prime gap between proven primes is 1,113,106. The two successive primes at either end have 18662 digits each. A larger gap, of 3,311,852 numbers between probable primes has been conjectured.
Prime numbers up to one hundred?
There are 25 of them. Here's an easy way to find them:-- Write down all the numbers from 1 to 100.-- Cross out all the even numbers except '2'.-- Cross out all the numbers with digits that add up to a multiple of '3', except '3'.-- Cross out all the numbers that end in '5', except '5'.-- Cross out any others that can be divided evenly by any number other than '1' and themselves.-- The 25 remaining numbers are the primes you're looking for.I told you it was easy !
What do all prime numbers end with?
After 5, all prime numbers end with 1, 3, 7 or 9.
