An estimate of $E>0$ earns $\left\lfloor 20 \min \left(\frac{N}{E}, \frac{E}{N}\right)\right\rfloor$ points. One heuristic for estimating the answer is that numbers of the form p^{q} r^{s}$for primes$p, q, r, s$with$p $\neq$ r, q $\neq$ s$ are primest. Thus, primest numbers are not very rare, so we can expect the answer to be relatively small with only a few distinct prime factors.