4921373domain: NPropertiesPrimalityPrimeyesAppears in sequencesSmallest number requiring n steps to reach 0 when iterating the function: f(n)=abs(lpd(n)-Lpf(n)), where lpd(n) is the largest proper divisor of n and Lpf(n) is the largest prime factor of n.at n=21A074347Prime numbersat n=343376