Respuesta :

First let's find the factors of each number:
19: 1,19
21: 1,3,7,21
23: 1,23
25: 1,5,25
21 has 4 factors, 25 has 3 and 23 and 19 are both prime numbers (with two factors).  21 has the most factors.
gisselgarciag17

Answer:

21

Step-by-step explanation: