golang into to byte array (as string formation)

intToByteArrayAsString.go

package main

import "fmt"

func main(){
  number := 514235
  fmt.Println("original number\t\t\t\t", number)
  
  numArr := IntToByteArray(number)
  fmt.Println("number as byte array\t\t", numArr)
  fmt.Println("number as string (control).\t", string(numArr))
}

func IntToByteArray(num int) []byte {
	if num == 0 {
		return []byte{48}
	}
	old := num
	arr := make([]byte, 0, 8)
	for num > 0 {
		old = num
		num = num / 10
		arr = append(arr, byte(old-num*10+48))
	}
	for i := 0; i < len(arr)/2; i++ {
		arr[i], arr[len(arr)-i-1] = arr[len(arr)-i-1], arr[i]
	}
	return arr
}