Split string on the first white space occurrence

Question

I didn\'t get an optimized regex that split me a String basing into the first white space occurrence:

var str=\"72 tocirah sneab\";

I need

Answer 1

var arr = [];             //new storage
str = str.split(' ');     //split by spaces
arr.push(str.shift());    //add the number
arr.push(str.join(' '));  //and the rest of the string

//arr is now:
["72","tocirah sneab"];

but i still think there is a faster way though.