Prime Numbers

2 x 3 x 3 x 5 x 5 = 450

two

The prime power factorization of 81 is 34.

There are three: 2, 5 and 23.

153 = 3 x 3 x 17

13 can divide 169.

Use a factor tree.

50

25,2

5,5,2

No. Any factor string of a negative number would have to include at least one negative number and there aren't any negative prime numbers.

No.

The least prime factor of 700 is two (2).

Any number with more than two factors

-- If you accept decimals and fractions, then there are an infinite number of pairs that

satisfy that description.

-- If you only want to consider whole numbers, then there are only two possible pairs:

1 and 13

-1 and -13

A straight line on the number line.

one

Yes.

78

39,2

13,3,2

2 x 3 x 13 = 78

If you don't finish the question, we can't finish the answer.

A primality test is an algorithm for determining whether an input number is prime, but I'm willing to bet that a lot of mathematicians type "prime number calculator" into their web browsers.

241 is a prime number. Any number that only has itself and one as factors is a prime number. Therefore, since there are no factors of 241 other than one and itself it is a prime number.

2 x 2 x 3 x 3 x 5 = 180

2 x 2 x 2 x 5 x 5 = 200

2 x 2 x 2 x 3 x 3 x 5 = 360

421 is a prime number so it does not have prime factorization.

The prime factors of 91 are 7 and 13. 13 is a prime number so only has 1 and itself as factors. Therefore the only common factors for 13 and 91 are 1 and 13.

2 x 2 x 11 = 44

1000

It will take four: 2 x 5 x 5 x 5