389

This number is a prime.

+ An Eisenstein prime with no imaginary part.

+ The smallest conductor of a rank 2 elliptic curve.

+ The smallest emirp equal the sum of the first two dozen consecutive idoneal numbers. [Loungrides]

+ The first in the smallest set of 4 consecutive primes (389, 397, 401, 409) that are congruent to 1 (mod 4). [Post]

+ The emirp whose common logarithm first exceeds its prime digital root. [Beedassy]

+ The smallest prime (emirp) whose sum of digits is an abundant number. [Loungrides]

+ The smallest emirp which is the sum of the digits of first emirps. [Silva]

+ The twentieth emirp (389) contains sum of digits equal to twenty. [Bajpai]

+ The only 3-digit Hyper-Cullen 2nd species prime (emirp), i.e., a prime of form n*2^n+(n-1), case n=6. [Loungrides]

+ The only prime (emirp) having 89 as a two-digit ending among the 3-digit primes. [Loungrides]

+ The product of the first four Fibonacci primes minus one. [Leonard]

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