Okay, Washington. What do we think? The city is running out of 202 telephone numbers. On Tuesday it was announced that the new, additional area code for the city will be 771.

Good number? Bad number? Just a number?

Seven-seven-one is only mildly interesting to Michael Raney, a mathematics professor at Georgetown University. It’s not a prime number, he pointed out, but it is a product of prime numbers. Multiply 3 times 257 and you get 771.

Three and 257 are Fermat primes, named after French mathematician Pierre de Fermat. You’ve probably heard of Fermat’s Last Theorem. This has nothing to do with that. (“He stuck his fingers in a lot of pies,” Raney said.)

Over at George Washington University, professor of mathematics Daniel Ullman noticed another property of 771. It is one of only three three-digit numbers that “have the property that the regular n-sided polygon can be constructed by straightedge and compass,” he said. The other numbers are 255 and 257.

Apparently, this property — called a constructible polygon — was known to the ancient Greeks. I, a modern American, have no idea what it means, but it’s also something that puts 771 in the category of “mildly interesting” as opposed to “earth shattering.”

So far, D.C.’s new area code — set to be rolled out by the end of 2022 — isn’t looking that auspicious. Of course, searching for hidden meaning in a number is not something sober mathematicians are inclined to do. Kabbalah isn’t going to help you when you need to estimate how much carpet you need for the rec room.

Said Ullman: “I liken numerology to mysticism and religious beliefs about numbers, which I don’t lend any credence to.”

And that, Dear Reader, is the perfect segue to Annie Larson, a psychic medium in Dulles, Va., who does reiki, astrology, tarot card reading and numerology (and who happens to have been born in Washington, at the old Walter Reed Hospital).

At my request, Larson examined 771.

“It really is interesting,” she said.

Larson said she typically works with numbers that are connected to a specific human: for example, a birth date or the letters in a person’s name converted to digits and added up. Looking at an area code is somewhat unusual.

Larson added up the three digits in 771 and arrived at 15. That is not a number that numerologists parse, she said. They focus on 1 through 9 (sometimes 0), and on what are known as master numbers: 11, 22 and 33.

Since 15’s no good, Larson added its digits. The answer: six. This is a propitious number, she said.

“With the number six, we’re looking at healing and nurturing and empathy and emotions,” Larson said. “If I look at it broader than that, I would start looking out toward astrology, looking at the Sixth House of astrology.”

That, she said, is associated with strength, employment and duty, along with sickness, wellness and health care.

Going back to the original number — 771 — seven is associated with business, diplomacy and equilibrium, Larson said. The number one is associated with new beginnings.

Put it all together and Larson’s conclusion is that the new 771 area code could presage Mitch McConnell’s worst nightmare: statehood, finally, for the District of Columbia.

Said Larson: “This may sound kooky — I’m a psychic medium — if you look at it with that new area code, it will probably bring the energy in of the 51st state.”

Add the five and one from 51 and what do you have? Six again.

“I think they picked very well,” Larson said of 771. “I think it’s a better area code than 202.”

The history of 202

The first local reference I could find to what we know today as the area code was in a 1946 article in the Evening Star. The story explained that nationwide dialing by long-distance operators was coming: “When this is adopted, American Telephone and Telegraph may divide the nation into 60 or 70 ‘numbering plan areas,’ each designated by a code.”

The following year, 202 was introduced as one of the country’s first area codes. Today there are more than 330 U.S. area codes.

People get possessive about their telephone numbers. Washingtonians were upset in 1961 when C&P Telephone announced it was switching from the old alphabetical exchanges that gave phone numbers a nice ring, i.e.: COlumbia 6-4320 or REpublic 5-7700.

The trouble with words, the company explained, was that so many combinations were ruled out. “The 9-5 combination (WXY and LKJ) is an especially pesky customer,” The Washington Post explained in an editorial. “The only known word assembled from this unhappy complex, so we learn, is ‘Ylang,’ which, if you didn’t know, is a species of Philippine tree.”

The phone company estimated that by abandoning the letters it could get 25 percent more numbers.

Of course, we are increasingly defined by numbers. In 1997, the 240 area code was added to the 301 area code in Maryland. In 2000, 571 was grafted onto 703 in Northern Virginia.

Soon, 771 will join them.

Twitter: @johnkelly

For previous columns, visit washingtonpost.com/john-kelly