(multiplication of all alphabet numbers)-(addition of odd number alphabets)

a=1,b=2,c=3,d=4,e=5,f=6,g=7,h=8,i=9,j=10,k=11,l=12,m=13,n=14,o=15,p=16,q=17,r=18,s=19,t=20,u=21,v=22,w=23,x=24,y=25,z=26

arjun= (1*18*10*21*14)-(1+21)=52898

gaurav=(7*1*21*18*1*22)-(7+1+21+1)=58182

similarly

vedan=(22*5*4*1*14)-(5+1)=6154....

so answer is 6154...