How to use Random number in Jenkins Declarative pipeline

Can someone please help me how to use random numbers in jenkins declarative pipelines as a environment variable to use this number in whole pipeline, we need this number to use as a tag to my build artifact. Thank you.

I tried below in my Jenkins declarative pipeline but it throws null message

environment {
          rand = "$RANDOM"
}

stages{
    stage("number"){
     steps{
       script{
               echo " this is a number $rand"
}}}}

Here is the pipeline script, to generate random number:

pipeline {
    agent any
    
    environment {
        max = 50
        random_num = "${Math.abs(new Random().nextInt(max+1))}"
    }
    
    stages {
        
        stage('Randon number') {
            steps {
                echo "The random number is: ${env.random_num}"
            }
        }
        
    }
    
}

This will generate random numbers between 0-50.

Here you can change the value of the max to decide the upper limit range.