21720-87-6 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 21720-87-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,1,7,2 and 0 respectively; the second part has 2 digits, 8 and 7 respectively.
Calculate Digit Verification of CAS Registry Number 21720-87:
(7*2)+(6*1)+(5*7)+(4*2)+(3*0)+(2*8)+(1*7)=86
86 % 10 = 6
So 21720-87-6 is a valid CAS Registry Number.