The CAS Registry Mumber 4859-72-7 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 4,8,5 and 9 respectively; the second part has 2 digits, 7 and 2 respectively. Calculate Digit Verification of CAS Registry Number 4859-72: (6*4)+(5*8)+(4*5)+(3*9)+(2*7)+(1*2)=127 127 % 10 = 7 So 4859-72-7 is a valid CAS Registry Number.