# 138

This number is a composite.

Concatenate the first two prime factors of 138 to get the third. [Cramer]

138 is the only three-digit number m such that π(m) and prime(m) are palindromic numbers. [Firoozbakht]

Arithmetic mean of the first eighteen emirps. [Bajpai]

(There are 4 curios for this number that have not yet been approved by an editor.)

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