Investing in dividend stocks is a proven wealth-building strategy, but with the stock market hovering near record highs on encouraging economic data, income investors aren't sure if there are any bargain dividend stocks left out there.

Believe it or not, some top-notch dividend stocks are still embarrassingly cheap given the potential growth ahead in their dividend and stock price. The three dividend growth stocks below will definitely make you sit up and take notice. 

A woman points to a line on a spreadsheet while looking at a computer monitor with a man.

Image Source: Getty Images.

A perfect time to check out this 7.4%-yielding stock 

With most oil stocks shooting through the roof this year thanks to rising crude oil prices, you might think you'd burn your finger if you dip into any right now. That may not be true, as top-notch dividend-paying stock Enterprise Products Partners (EPD 0.18%) and its hefty 7.4% appears too cheap to pass up.

As a midstream company, Enterprise Products Partners is among the safest stocks to bet on in the oil and gas industry. Its predictable cash flows that aren't subject to volatile oil prices also lay the foundation for stable, regular, and rising dividends. Enterprise Products Partners has increased its dividend every year for 22 consecutive years now, and grown it at a compound annual rate of 7% through the period, which is impressive given the volatility and cyclicality of the energy sector.

As proof of its resilience, Enterprise Products Partners' cash flows covered dividends 1.6 times even in a historically challenging year for oil companies like 2020. With oil prices on the rise and the company's capital spending on the decline, its cash flows and dividends are primed to grow. The stock, though, is still nearly 20% off its January 2020 level when oil prices were much lower and it's trading below its five-year average price-to-cash flow, which tells me Enterprise Products is not only one of the safest energy dividend stocks right now, but also really cheap.

This alluring dividend stock is also a megatrend play

Brookfield Renewable (BEP 1.63%) (BEPC 1.56%) is a top-notch player in a trillion-dollar industry and is paying world-class dividends, but the stock has been out of favor with investors in recent months.

Shares of Brookfield Renewable Corporation (which trade under ticker BEPC) have dropped a lot more than the units of limited partnership (LP) Brookfield Renewable Partners (ticker BEP), but here's the thing: Demand for shares of the corporate entity soared soon after it was formed thanks to the tax advantages of owning them versus owning units of the LP, but that's practically the only difference between the two. They're the same entity with the same growth catalysts and the same dividends, and their yields have also converged at around 3% currently.

BEP Chart

BEP data by YCharts

So far, Brookfield Renewable's growth has been driven largely by growth in its funds from operations (FFO), and the trend should continue. So between 2010 and 2020, the company grew FFO and dividends at a compound annual growth rate of 10%. Through 2025, Brookfield foresees 6% to 11% organic growth in FFO, and an additional 4% to 5% growth through potential acquisitions. That should drive dividends and share price.

Brookfield's growth catalysts are, in fact, already firmly in place. Renewable energy is undeniably the future of energy, and Brookfield already has unparalleled clout in hydropower even as it expands aggressively into solar and wind, which is reflecting in its rapidly growing backlog. Given the potential income and dividend growth, Brookfield appears to be one of those top underrated stocks poised for a rebound

With more than six decades of dividend increases, why doubt this stock?

3M (MMM 0.57%) shares have been under pressure ever since they got whacked right after the company released its first-quarter earnings at the end of April. If you look carefully at 3M's numbers and prospects though, the stock looks really cheap. Take a look at the chart below:

MMM Cash from Operations (TTM) Chart

MMM Cash from Operations (TTM) data by YCharts

3M didn't just bounce back quickly after taking a big hit from the coronavirus lockdowns in 2019; it's generating higher cash flows than ever, which it used to repay debt worth $450 million that was due for maturity in 2022. The company also increased its dividend by 1% in the first quarter. Though it was small, the dividend hike reflects 3M's resilience during tough times, and it marked the industrial giant's 63rd straight annual dividend increase. And in the one year through the first quarter alone, 3M cut down its debt by nearly $5 billion.

Investors were miffed when 3M didn't raise its full-year guidance despite a strong first quarter, but I'm not complaining about 3M being conservative about its outlook as long as it's growing: 3M expects 5% to 8% growth in sales and expects to earn $9.20 to $9.70 per share versus the $9.25 it earned in 2019, backed by growth across all its segments -- safety and industrial, transportation and electronics, healthcare, and consumer.

Importantly, 3M expects to convert nearly all of its net income into free cash flow this year, which means its cash flows should trend even higher. Yet, the stock is trading well below its five-year average price-to-cash flow, making it one of the cheaper Dividend Kings out there.