What do Apple and some well-off senior citizens have in common? Financial quirks are helping them get richer.

Apple first.

If you look at the interest rates on Apple’s $14 billion borrowing early this month, it becomes instantly obvious why the company went to the debt market to raise money to buy back stock rather than tapping into its $200 billion or so of cash and marketable securities.

It’s because the interest rate on Apple’s new debt is incredibly low. Especially on the $2.5 billion of five-year notes, which carry a lower after-tax interest cost for Apple than the after-tax cost of the cash dividend that it pays its common stockholders.

That sounds unbelievable, doesn’t it? But let me show you the numbers, and you’ll see that it’s true.

The interest rate on Apple’s $2.5 billion, five-year notes is 0.7 of one percent. That interest is tax-deductible for Apple, so after applying the 21 percent federal corporate tax rate, Apple’s net interest cost is 0.55 percent.

The yield on Apple’s common stock, when last I looked, was about 0.65 percent. (That’s Apple’s 82-cent annual dividend divided by its recent stock price of about $127.) However, the dividend isn’t tax-deductible to Apple.

So, you see, Apple’s after-tax cost of that $2.5 billion five-year borrowing is less than the after-tax cost of the dividends that it won’t have to pay on stock it buys back with that borrowed money.

Given that Apple is rapidly increasing its annual cash dividend — it’s risen to its current 82 cents from 52 cents five years ago — the savings to Apple from buying in shares now will likely increase over time.

Now, to money falling from the sky for some senior citizens — who happen to include me.

Here’s the deal. If you’re 72 or older and own one or more defined contribution retirement plans such as 401(k)s, 403(b)s or individual retirement accounts, you’re obliged to take “required minimum distributions” each year. Your RMD is based on your year-end age and the year-end balance in your accounts.

For example, if you were 75 years old this past Dec. 31 and your account balances totaled $100,000, you’re required to take at least $4,367 in distributions, which are federally taxable, this year.

Now, let’s say you want to contribute $1,000 to your local food pantry. You can make that donation by writing a $1,000 check to the pantry from one of your IRAs (but not from a 401(k) or 403(b) ) or by having your IRA administrator issue a $1,000 qualified charitable distribution check made out to the pantry. That would reduce your required taxable distribution by $1,000 — the functional equivalent of getting a federal tax deduction for your contribution.

If, like me and the vast majority of taxpayers these days, you’re taking the standard deduction, this is money falling from the sky.

Last March, after stocks tanked more than 30 percent from their then-all-time highs a month earlier, Congress canceled RMD requirements for 2020 as part of the Coronavirus Aid, Relief, and Economic Security Act, or Cares Act. That meant that you got no tax advantage last year by using qualified charitable distributions to make contributions.

This year, RMDs are back. And so is the attractiveness of using QCDs. In fact, my first financial move this year was ordering 18 QCD checks, mostly to charities that I told last year they’d be getting my 2020 contributions in early 2021 because I couldn’t deduct them in 2020.

There are all sorts of limits and complications involved with QCDs, which we’ll discuss another day. You also have to keep track of how much in QCDs you’ve made and make sure that you or your tax preparer subtract your QCDs from the retirement income shown on the 1099-R forms you get from your plans’ administrators.

Sure, the paperwork and some of the other QCD rules are annoying. But when money is falling from the sky, annoyance is a cheap price to pay for getting your buckets filled.