Golang: Random 6 Digit http://play.golang.org/p/tKvAnqvhrm

rand_six_int.go

package main

import (
	"crypto/rand"
	"log"
	"math/big"
)

func sixDigits() int64 {
	max := big.NewInt(999999)
	n, err := rand.Int(rand.Reader, max)
	if err != nil {
		log.Fatal(err)
	}
	return n.Int64()
}

func main() {
	for i := 0; i < 100; i++ {
		s := sixDigits()
		log.Printf("%06d\n", s)
	}
}