It has 2098967 decimal digits. See record page here.
3^1681130 + 3^445781 + 1 is prime.
Proof file: HERE Record page here. 3^1681130+3^445781+1 has 802,104 digits factor of p-1: 3^1681130+3^445781 = 3^445781*(3^1235349+1) for 3^1235349+1: Divisor of 1235349: {1, 3, 9, 317, 433, 951, 1299, 2853, 3897, 137261, 411783, 1235349} for which Cyclotomic[2x,3] divides 3^1235349+1, 3^1235349+1=Product of Phi[2m,3], m is in the above divisor list. Phi: Cyclotomic function in Mathematica. Phi[2,3] = […]
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