For a non-unit a of an atomic monoid H we call $L_H(a) = {k ∈ ℕ | a = u₁... u_k with irreducible u_i ∈ H}$ the set of lengths of a. Let H be a Krull monoid with infinite divisor class group such that each divisor class is the sum of a bounded number of prime divisor classes of H. We investigate factorization properties of H and show that H has sets of lengths containing large gaps. Finally we apply this result to finitely generated algebras over perfect fields with infinite divisor class group.