public boolean isPerfectNumber(long number) {
		boolean b = false;
		List<Long> factorList = new ArrayList<Long>();
		long remain = number;
		for (long i = 1; i < (number/2+1); i++) {
			if (number % i == 0) {
				factorList.add(i);
				remain -= i;
				if (remain < 0) {
					break;
				}
			}
		}
	    b = remain == 0;
	    if(b){
	    	System.out.println("Number " + number + " is a perfect number, factors are : " + combind(factorList,", "));
	    }
	    return b;
	};