Display PHP Version in WordPress Admin Footer

wordpress-display-php-version-admin-footer-functions.php

<?php
/* Display the current PHP version in the footer of WP Admin
 * Simply add this code to your child theme's functions.php
 */
function change_footer_version() {
  return sprintf( 'WordPress %s &bull; PHP %s', get_bloginfo( 'version' ), phpversion() );
}
add_filter( 'update_footer', 'change_footer_version', 9999 );