2219844666811981651

This number is a composite.

                                                        221984466 6811981651

Just showing those entries submitted by 'Luhn': (Click here to show all)

Call this number p and you get the offset d, where 10^319+d starts the smallest 320-digit prime septuplet for the pattern {0,2,6,8,12,18,20}. [Luhn]