55555...55557 (88-digits)
This number is a prime.
55555555 5555555555
5555555555 5555555555 5555555555 5555555555 5555555555 5555555555 5555555557
Just showing those entries submitted by 'Bajpai': (Click here to show all)
The largest near-repdigit prime p smaller than a googol found in the sequence 7, 57, 557, 5557, 55557, 555557, 5555557, etc. Curiously, p is also expressible as the sum of two squares. [Bajpai]
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