31
15.5 x 2 = 31
asdasd
They are: 1*31 = 31 which is a prime number
4 and 27
31 is a prime number. So the only way you could get 31 is 1X31.
271
961
15.50 * 31 = 480.5
31 multiplied by 7 is 217
31 multiplied by 29 is 899.
786 multiplied by 31 = 24,366