The public key Rivest Shamir Adleman (RSA) algorithm is one of The powerful cryptosystem which was adopted by a wide variety of applications that needs secure communications of RSA lays in the complexity of factoring large number N into two prime numbers p and q (N= p* q) in reasonable time. The time for factoring such a number increases as p or q bigger and lies at the end of the problem search space. The Personal Computer standard data types in languages: can not store large number N with the length for more than 10 decimal digit. This project solved this problem by storing the number as string, and factor the number N up to 14 decimal digits by using two approaches the first approach is a simulation to Parallel computing which is represented by using a pool of threads to speed up the factorization process the thread granted by a modern operating system (Windows environment). The second approach by using a Hetroassociative neural network which is trained by using a Hebb rule to recognize a pattern of bits that represent the number N and produce the prime numbers p and q. The neural network approach used for numbers of lengths 10 decimal digits or less, for the time limitation of preparing this project.