Binary representation of a number is palindrome or not?

Python - 46 chars

n=bin(input())[2:]
print'YNEOS'[n!=n[::-1]::2]

Golfscript -- 22 chars

~2base.-1%="YES""NO"if

C 84 81 74 Characters

r;main(v,x){for(scanf("%d",&v),x=v;v;v/=2)r=r*2|v&1;puts(r-x?"NO":"YES");}

It does not use any function like string reverse.