721-40-4 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 721-40-4 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 7,2 and 1 respectively; the second part has 2 digits, 4 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 721-40:
(5*7)+(4*2)+(3*1)+(2*4)+(1*0)=54
54 % 10 = 4
So 721-40-4 is a valid CAS Registry Number.