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Herald Reporter

Today’s date in the logical DDMMYYYY eight-digit format we use, sequencing the day of the month, the month and then the year, is 22022022. It reads the same forwards, backwards and, using the digital number glyphs based on a barred square, the same upside down.

This makes it the rare double, both a palindrome, which means it reads the same forwards and backwards, and an ambigram, which means it reads the same upside down. The next one that is both in the eight-digit DDMMYYYY system and digital font glyphs is some way off, 8 February 2080.

There are in fact 11 such dates this century in our eight-digit date convention, but today is the eighth and the other three are all in the 2080s.

Today’s date is also both in the equally logical Japanese convention of YYYYMMDD, a decreasing sequence but still in order, but not in the American convention of MMDDYYYY since the Americans, unlike the Japanese and most of the world, put the day number between the month number and the year number. In fact all DDMMYYYY dates that are both are also obviously both in the Japanese convention.

The last double was fairly recent, 12 February last year, or 12022021, for non-Americans and Japanese and 2 December last year, same digit sequence, for Americans.

The double requires not only a palindrome in the eight-digit format, such as 4 February 2040 or 04022040, but also one using only the four digits that have rotational symmetry in the digital glyphs, that is 0, 1, 2 and 8.

We will have 29 palindromes in our date convention, and the Japanese date convention, this century, because conventions insist on only February dates being candidates for a palindrome since the month must be 02 to match the 20 in the first two digits of the year, only 11 of those palindromes are also ambigrams since these are the only palindromes that use dates that include just 0, 1, 2 and 8.

Although most Februarys have only 28 days we win the 29th palindrome because 2092 is a leap year and so 29022092 works.

This means there were a cluster of dates that were both palindromes and ambigrams in some Februarys in the early decades of the 21st century the clustering coming from the fact that three of the four permitted numbers are the first three numbers. That “8” shoves the final three into the 2080s.

When we work out what dates are both palindromes and ambigrams we need to look at the 1st, 2nd, 8th, 10th, 11th, 12th, 18th, 20th,21st, 22nd and 28th of February to get a list of dates that are both palindromes and ambigrams this century.

So taking those 11 dates and ordering them in sequence we have had 10022001, 20022002, 01022010, 11022011, 21022012, 02022020, 12022021 and now 22022022 and we can look forward to 08022080, 18022081, and 28022082 as the eight comes into play.

Americans have far fewer since although they get a bit luckier on months since they can use January, February, August October, November and December dates this century as those months use symmetrical digits and they shove the month at the beginning. But their list requires the day number to end in 02 to get the 20 of the start of the year. This limits them to the second of the month, and

with six months that gives them just six dates that are both: 10022001, 01022010, 11022011, 02022020, 12022021, 08022080. They too have to wait until the 2080s for their next one.

When it comes to palindromes without the extra condition they are still stuck with the second of the month, but can use all 12 months, so they get 12 palindromes although only those six are also ambigrams.

Some people think palindromes are lucky, and so there are in some cultures a large cluster of weddings on those days. Once we move down to missing the zeros at the start of the numbers for the day and the month, and limit the year to the final two digits we can have four to six digits in a date and that can generate a lot of what are termed minor palindromes.

But presumably the full eight-digit palindrome is luckier and presumably being an ambigram as well makes it even luckier. So those born today might well be under a bright star.