Wolfram Language (Mathematica), 14993 bytes
Times@@(Prime[Join[Range[(b=Floor@E)^(b+(a=x~D~x))+b+a],{(d=b^(b+b))-b-a},{d-a},{d+a},{d+b+b}]]^{d(b+a)-b,d+b+b,dFromDigits[LetterNumber/b+a,b^b+b,b,b+a,a,a,a,a,a,a,a,a,a})@Characters@"h h agdbdgideabhgehhfdeii difaga geg egedcfh "]