A downtrend has been apparent in 360 DigiTech, Inc. Sponsored ADR (QFIN) lately with too much selling pressure. The stock has declined 34.8% over the past four weeks. However, given the fact that it is now in oversold territory and Wall Street analysts are majorly in agreement about the company's ability to report better earnings than they predicted earlier, the stock could be due for a turnaround.How to Determine if a Stock is OversoldWe use Relative Strength Index (RSI), one of the most commonly used technical indicators, for spotting whether a stock is oversold. This is a momentum oscillator that measures the speed and change of price movements.RSI oscillates between zero and 100. Usually, a stock is considered oversold when its RSI reading falls below 30.Technically, every stock oscillates between being overbought and oversold irrespective of the quality of their fundamentals. And the beauty of RSI is that it helps you quickly and easily check if a stock's price is reaching a point of reversal.So, by this measure, if a stock has gotten too far below its fair value just because of unwarranted selling pressure, investors may start looking for entry opportunities in the stock for benefitting from the inevitable rebound.However, like every investing tool, RSI has its limitations, and should not be used alone for making an investment decision.Here's Why QFIN Could Experience a TurnaroundThe RSI reading of 28.31 for QFIN is an indication that the heavy selling could be in the process of exhausting itself, so the stock could bounce back in a quest for reaching the old equilibrium of supply and demand.This technical indicator is not the only factor that calls for a potential rebound for the stock. There is a fundamental indicator as well. A strong agreement among sell-side analysts covering QFIN in raising earnings estimates for the current year has led to an increase in the consensus EPS estimate by 8.1% over the last 30 days. And an upward trend in earnings estimate revisions usually translates into price appreciation in the near term.Moreover, QFIN currently has a Zacks Rank #1 (Strong Buy), which means it is in the top 5% of more than the 4,000 stocks that we rank based on trends in earnings estimate revisions and EPS surprises. This is a more conclusive indication of the stock's potential turnaround in the near term. You can see the complete list of today's Zacks Rank #1 (Strong Buy) stocks here >>>> Breakout Biotech Stocks with Triple-Digit Profit Potential The biotech sector is projected to surge beyond $775 billion by 2024 as scientists develop treatments for thousands of diseases. They’re also finding ways to edit the human genome to literally erase our vulnerability to these diseases. Zacks has just released Century of Biology: 7 Biotech Stocks to Buy Right Now to help investors profit from 7 stocks poised for outperformance. Our recent biotech recommendations have produced gains of +50%, +83% and +164% in as little as 2 months. The stocks in this report could perform even better.See these 7 breakthrough stocks now>>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report 360 DigiTech, Inc. Sponsored ADR (QFIN): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research