The CAS Registry Mumber 186392-22-3 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,8,6,3,9 and 2 respectively; the second part has 2 digits, 2 and 2 respectively. Calculate Digit Verification of CAS Registry Number 186392-22: (8*1)+(7*8)+(6*6)+(5*3)+(4*9)+(3*2)+(2*2)+(1*2)=163 163 % 10 = 3 So 186392-22-3 is a valid CAS Registry Number.