10 PRINT "Enter a number."
20 INPUT N
25 PRINT "------"
30 IF N<0 THEN LET N = -N
40 IF N<2 THEN END
50 LET I = 2
60 IF I*I > N THEN GOTO 200
70 IF (N/I)*I = N THEN GOTO 300
80 LET I = I + 1
90 GOTO 60
200 PRINT N
210 END
300 LET N = N / I
310 PRINT I
320 GOTO 50