18181
This number is a prime.
Just showing those entries submitted by 'Bajpai': (Click here to show all)
18181 is strobogrammatic and well as a tetradic prime. [Bajpai]
The only palindromic prime P that is the sum of the squares
of the first n oban numbers, i.e., (3^2 + 5^2 + 6^2 +...+
39^2 + 50^2), (case n=30). Curiously, sod(P) is the
smallest invertible prime. [Bajpai]
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