<?php
error_reporting(-1);
 
$regexp = '/^(8|[+][ ]*7)([() -]?[0-9][() -]?){10}$/u';
$trash = '/[() -]/u';
$pureText = '+7(812)67)8 -67(67';
$anotherTrash = '/^[+]7/u';
$text = preg_replace($anotherTrash, '8', $pureText); 
 
if(preg_match($regexp, $text)){
	$pureNumArray = preg_split($trash, $text);
		foreach($pureNumArray as $Num){
		$pureNum = $pureNum . $Num;
	};
	echo "Ваш номер {$pureNum}\n";
}else{
	echo "Введенный номер неверен\n";
};

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