A random number generator (1, 2), comprising: a static random number generator comprising an initial random number pool and a static random number pool, and configured to output a static random number sequence (Ssrn) from one of the initial random number pool and the static random number pool; at least one dynamic entropy source (12 to 12) configured to generate an dynamic entropy bit (one of E to E); a counter coupled to the at least one dynamic entropy source (12 to 12) and configured to generate a dynamic random number sequence (Sd) according to the dynamic entropy bit (one of E to E); and a combining circuit coupled to the static random number generator and the counter, and configured to receive the static random number sequence (Ssrn), and output a true random number sequence (Strn) to a lively random number pool according to the static random number sequence (Ssrn) and the dynamic random number sequence (Sd); wherein the static random number pool is configured to be updated when the lively random number pool is fully updated; during an operation phase, the static random number pool is further configured to generate a subsequent static random number sequence (Ssrn), and the combining circuit is further configured to generate a subsequent true random number sequence (Strn) according to the subsequent static random number sequence (Ssrn) and a subsequent dynamic random number sequence (Sd), and update the lively random number pool according to the subsequent true random number sequence (Strn); and the static random number sequence (Ssrn) has a hamming weight of substantially 50%, a hamming distance of substantially 50% and a min-entropy of substantially 1. a static random number generator comprising an initial random number pool and a static random number pool, and configured to output a static random number sequence (Ssrn) from one of the initial random number pool and the static random number pool; at least one dynamic entropy source (12 to 12) configured to generate an dynamic entropy bit (one of E to E); a counter coupled to the at least one dynamic entropy source (12 to 12) and configured to generate a dynamic random number sequence (Sd) according to the dynamic entropy bit (one of E to E); and a combining circuit coupled to the static random number generator and the counter, and configured to receive the static random number sequence (Ssrn), and output a true random number sequence (Strn) to a lively random number pool according to the static random number sequence (Ssrn) and the dynamic random number sequence (Sd); wherein the static random number pool is configured to be updated when the lively random number pool is fully updated; during an operation phase, the static random number pool is further configured to generate a subsequent static random number sequence (Ssrn), and the combining circuit is further configured to generate a subsequent true random number sequence (Strn) according to the subsequent static random number sequence (Ssrn) and a subsequent dynamic random number sequence (Sd), and update the lively random number pool according to the subsequent true random number sequence (Strn); and the static random number sequence (Ssrn) has a hamming weight of substantially 50%, a hamming distance of substantially 50% and a min-entropy of substantially 1.