Number fans are excited to see that today's date when written as a number is both a palindrome and an ambigram.
That means that when it is read from either right to left or left to right it is the same 22022022.
What's more it can also be read the same when turned upside down.
It's led to some people dubbing the day Twosday – because the date can be written as all twos 22.2.2 and it falls on a Tuesday. February 22, won't be a Tuesday again for another 400 years.
Elsewhere, the date has become known as Duck Day because, as any bingo fan knows, the number two can look like a duck hence the call for 22 as "two little ducks".
This is not the first time a date is both a palindrome and an ambigran – it happened in 1111 too, as Stonehenge mentioned on social media.
There's eager anticipation of when it gets to 10.22pm. In the 24 hour clock the date and time would then read as 22:22 22.2.22 or 22:22 22.02.2022 depending on the date format, although the longer version would no longer be a palindrome if the time is included.
According to timeanddate.com there are up to 10 palindromes in February, but only if you go with the date format as favoured in the US which puts the month first m:dd:yy.
For example, February 23, 2022, could be written as 2.23.22.
While Stonehenge was looking back at onesday, the University of Oxford shared its appreciation for an upcoming palindrome date.
February 29, 2092. It will be the last palindrome of the century and fall on a leap day.
A date for the diary then, along with that Tuesday in 2422.