title: How can I convert a *big.Int into a byte array in golang
body: <p>Im trying to do calculations on a big int number and then convert the result to a byte array, but I cannot figure out how to do so this is where Im at so far. anyone got any ideas</p>
  
  <pre><code>sum := big.NewInt(0)
  
  for _, num := range balances {
      sum = sum.Add(sum, num)
  }
  
  fmt.Println("total: ", sum)
  
  phrase := []byte(sum)
  phraseLen := len(phrase)
  padNumber := 65 - phraseLen
  </code></pre>