The CAS Registry Mumber 107588-83-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,7,5,8 and 8 respectively; the second part has 2 digits, 8 and 3 respectively. Calculate Digit Verification of CAS Registry Number 107588-83: (8*1)+(7*0)+(6*7)+(5*5)+(4*8)+(3*8)+(2*8)+(1*3)=150 150 % 10 = 0 So 107588-83-0 is a valid CAS Registry Number.