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<?php $number = '+421917982116'; $haveNumberPlus = strpos($number, '+'); var_dump(!$haveNumberPlus); if (!$haveNumberPlus === false) { echo number_format((int)$number, 0, ' ', ' '); } echo '+' . number_format((int)$number, 0, ' ', ' ');

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55.87 ms | 402 KiB | 5 Q