administraCursos/database/factories/ProfessorFactory.php

<?php

/* @var $factory \Illuminate\Database\Eloquent\Factory */

use App\Professor;
use Faker\Generator as Faker;

$factory->define(Professor::class, function (Faker $faker) {
    return [
        'num_prof'      => $faker->numerify('#########'),
        'first_name'    => $faker->firstName(),
        'last_name'     => $faker->lastName(),
        'email'         => $faker->email,
        'type'          => null,
        'dept_id'       => 1,

    ];
});