This Week is full of Palindrome Dates

A palindrome is a word, phrase, or numerical sequence that reads the same from left-to-right or right-to-left. Simple words such as mom, dad, civic, and kayak are palindromes, as are names such as Bob, Anna, Elle, and Hannah. Even everyday internet-speak such as LOL is an easy palindrome.

But palindromes can be dates too. Dr. Aziz S. Inan, an electrical engineering professor at the University of Portland, Oregon, has been studying palindrome calendar dates for more than a decade. Last year, he alerted us of the 22 palindrome dates in 2021, and recently advised us about the many numerical palindromes in 2022.

Based on Dr. Inan’s findings and love for all things numbers, February 2022 will contain 10 palindrome dates, with a few extra fun or amazing plays on the number two.

February’s Ten Palindrome Dates in Month-Day-Year date format Include:

2-2-22
2-20-22
2-21-22
2-22-22
2-23-22
2-24-22
2-25-22
2-26-22
2-27-22
2-28-22

Note that the last nine five-digit palindrome dates are consecutive. If 2022 was a leap year, there would have been one more five-digit palindrome date in the sequence: 2-29-22 (2024 is the next leap year).

As you know, here in the US we write dates in the following format: Month-Day-Year. In Europe, many countries write the date in this format: Day-Month-Year. And in other areas of the world, the year comes first: Year-Month-Day.

With these three date formats in mind, it’s exciting to point out that this February, there will be 2 separate ubiquitous palindrome dates, that is, palindrome dates that occur on the same day of the calendar regardless of the date format being used:

One involving four digits of 2 occurs on Groundhog’s day: 2-2-22; 2-2-22; and 22-2-2

The other involving five digits of 2 coincides with George Washington’s Birthday: 2-22-22; 22-2-22; and 22-2-22

What’s more, 2-22-22 is a Tuesday for a bit of homophone fun (“2”sday).

Our founding father’s birth anniversary is also an eight-digit palindrome date this year when written as a full date in Day-Month-Year format: 22-02-2022. Additionally, 2-hundred years later, Washington’s birthday will be one-of-a-kind seven-digit palindrome date in each date format:
2-22-2222; 22-2-2222; and 2222-2-22.

If that wasn’t enough twos to boggle your mind, there’s another date that’s sure to please: 2-20-22. If written as a full date with all the year digits, this day is actually going to be a seven-digit palindrome date: 2-20-2022.

In places where Day-Month-Year (or Year-Month-Day) date format is used, there are even more palindrome dates to enjoy in 2022. In fact, there is one five-digit palindrome date that occurs on the 22nd day of every month between January and September, a four-digit one on the 2nd of February, and a six-digit one to occur on the 22nd day of November.

22-1-22
2-2-22
22-2-22
22-3-22
22-4-22
22-5-22
22-6-22
22-7-22
22-8-22
22-9-22
22-11-22

Dr. Inan loves to share such interesting dates with his students (and us) and finds numbers to be an art form. This is especially true when mathematical computations add even more numeric beauty to these unusual dates. “I wish I could live 22 hundred and 99 more years so I can experience the two one-of-a-kind seven-digit palindrome dates 1-23-4321 and 12-3-4321, since both of these dates will also be perfect square dates because 1234321 = 1111 x 1111!” Inan said.

Inan also points out that in Month-Day-Year date format there are 12 eight-digit and 26 seven-digit full palindrome dates (total 38) in the 21st century. In the Day-Month-Year date format, there are 29 eight-digit and 9 seven-digit full palindrome dates (again total 38) in the 21st century. See the list here.

Some cultures believe palindrome dates to be lucky. Which is why many people choose these dates for wedding celebrations. It also looks attractive to have the unique pattern of numbers appear on an invitation that’s a lifetime keepsake; dates such as 02-02-2020 or 11-11-11 were very popular dates for nuptials!

Special shout out to Dr. Inan who contributed much math and wisdom to this article.