The least common multiple of two different primes is 65. The two primes are______ And______ ．

The least common multiple of two different primes is 65. The two primes are______ And______ ．

65 = 5 × 13, answer: the least common multiple of two different prime numbers is 65, the two prime numbers are 5 and 13 respectively; so the answer is: 5, 13

Judge which of the following numbers are prime numbers and which are sum numbers (Mathematics)
19 32 28 75 108 39 59 305 111 23
Prime number:
sum:

Prime numbers: 19, 59, 23
Total: 32, 28, 75, 108, 39, 305, 111

Is this the right way to judge prime numbers?
Given a positive integer n
This method determines whether n is a prime
If n is not divisible by all prime numbers of 2 -- radical n
Then n is a prime

Think about it!
Must be: all numbers between 2 and root n
But, as long as the prime number is satisfied,
Because it can't be even, otherwise it can be divided by 2
Then it can't be a multiple of 3!