$(document).on("focus", "input", function() {
$(this).mask("(999) 999-99-99",{placeholder:"_"});
});
php > echo bcmul(6031, bcmul(8109, bcmul(980, bcmul(1909, bcmul(429, 1714, 0), 0), 0), 0), 0);
67275470345782378680
php > echo bcmul(8109, bcmul(980, bcmul(1909, bcmul(429, bcmul(1714, 6031, 0), 0), 0), 0), 0);
67275470345782378680
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