The number of primitive elements in a finite field GF(q) is φ(q − 1), where φ is Euler's totient function, which counts the number of elements less than or equal to m that are coprime to m. This can be proved by using the theorem that the multiplicative group of a finite field GF(q) is cyclic of order q − 1, and the fact that a finite cyclic group of order m contains φ(m) generators.