The CAS Registry Mumber 137465-86-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,3,7,4,6 and 5 respectively; the second part has 2 digits, 8 and 6 respectively. Calculate Digit Verification of CAS Registry Number 137465-86: (8*1)+(7*3)+(6*7)+(5*4)+(4*6)+(3*5)+(2*8)+(1*6)=152 152 % 10 = 2 So 137465-86-2 is a valid CAS Registry Number.