666666

This number is a composite.

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The larger of only two six-digit repdigit such that the product of itself and all truncations of itself plus one, i.e., 666666 * 66666 * 6666 * 666 * 66 * 6 + 1 = 78135326102739761857 is a prime. The other number is 444444. [Bajpai]

Submitted: 2016-03-22 07:20:40;   Last Modified: 2020-06-16 03:37:37.
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