I've actually written this exact program, although it was for the TI-83+ (and in TI-Basic.) However, I took a different approach.
Factors involve complicated thinking to me, so:
Take X, the value under the square root. If X % (Y*Y) == 0, then an answer is Y * sqrt(X) (since if X is divisible by Y squared, we can say sqrt(XYY) and pull the Y out of the radical.) I converted it to C (while sitting here):
Code:
#include <stdio.h>
#include <math.h>
int main()
{
int x, y;
printf("Enter a number: ");
scanf("%d", &x);
for(y = ceil(sqrt(x)); y > 1; y--)
{
if(x % (y * y) == 0) break;
}
printf("Simple form: %d * %c(%d)\n", y, 251, x / (y * y));
return 0;
}
That code has served me faithfully for many (ok, 2) years. The TI code was a bit more complicated (But also worked for cube roots, ect.). Now, if you want to literally output a 'sqrt' sign, that's a bit more complicated. You can output a 0xFB, which looks like a sqrt sign on the windows console. (But isn't very portable.) If you're in some GUI, the square root symbol is the unicode character U+221A.
sqrt(80000) = 200 * sqrt(2)
Although mine will fail on very large numbers. (>1.9B, shouldn't hurt too much.)