prime factorization of 405

Thanks Guys - both these answers have great value. 

I have added this question to reference material.

http://web2.0calc.com/questions/reference-material

The reference material thread is available for everyone.  It is one of the 'sticky' threads.    

Just type this into the on-site calculator  ....

factor(405)

Then....hit " =" 

Since 405 ends in 5, it is divisible by 5 --

405  =  5 x 81

Since 81 = 9 x  9 --

405  =  5 x 9 x 9

Since 9 = 3 x 3 --

405  =  5 x 3 x 3 x 3 x 3

Since those factors can't be reduced:

405  =  3⁴ x 5