} while (approxCmp > 0);
    } else {
      BigInteger nextPow = BigInteger.TEN.multiply(approxPow);
      int nextCmp = nextPow.compareTo(x);
      while (nextCmp <= 0) {
        approxLog10++;
        approxPow = nextPow;
        approxCmp = nextCmp;
        nextPow = BigInteger.TEN.multiply(approxPow);
        nextCmp = nextPow.compareTo(x);
      }
    }

    int floorLog = approxLog10;