First, to your direct question: "Is the record still 11", the answer is "yes", according to a variety of sources (MathWorld, Wikipedia, OEIS A003001). If anyone has found a new record, at least it is not in these sources yet.

Now for some general advice.

Finding a number that has high multiplicative persistence is a prime example of "hard to find, easy to verify". Given a (say) 500-digit number, it only takes a few lines of code, and an eyeblink of computer time, to compute its persistence.

My advice in such situations is:

*If you think you have succeeded in the difficult "find" task, surely you should spend a reasonable effort in the relatively easy "verify" task before announcing your result.*

So, if you think you have found such a small number with persistence 12, surely you should first verify your claim with some simple computer code. If that seems to succeed, perhaps double-check using another implementation, perhaps in a different language, perhaps on a different computer. After a reasonable amount of verification succeeds -- OK, perhaps then it is time to think about telling others.

The comments in OEIS claim various lower bounds on the size of a number of persistence 12: a comment in 2019 claims $10^{20585}$, and a comment in 2023 claims $2.67 \times 10^{30000}$. A 500-digit number would contradict both, so all the more reason to double-check.

For completeness, here is straightforward SageMath code to verify such claims. It can be run online in this SageMathCell.

```
def digits(n):
d = []
while n:
n, remainder = divmod(n, 10)
d.append(remainder)
return d
def multiplicative_persistence(n):
i = 0
print("%d: %d" % (i,n))
while n>=10:
n = prod(digits(n))
i += 1
print("%d: %d" % (i,n))
print("It has multiplicative persistence %d\n" % (i))
multiplicative_persistence(277777788888899)
multiplicative_persistence(10^500-1)
```

The output from these numbers is:

```
0: 277777788888899
1: 4996238671872
2: 438939648
3: 4478976
4: 338688
5: 27648
6: 2688
7: 768
8: 336
9: 54
10: 20
11: 0
It has multiplicative persistence 11
0: 99999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
1: 1322070819480806636890455259752144365965422032752148167664920368226828597346704899540778313850608061963909777696872582355950954582100618911865342725257953674027620225198320803878014774228964841274390400117588618041128947815623094438061566173054086674490506178125480344405547054397038895817465368254916136220830268563778582290228416398307887896918556404084898937609373242171846359938695516765018940588109060426089671438864102814350385648747165832010614366132173102768902855220001
2: 0
It has multiplicative persistence 2
```

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