439

This number is a prime.

+ A number that can be expressed as the signed sum of cubes in at least three ways: 2644883 + 3315743 - 3801933 = 23224043 - 8694183 - 22810573 = 4029063 - 2114023 - 3824893. [Rupinski]

+ The smallest prime such that another prime is never produced by inserting the same digit between each pair of its digits (40309, 41319, 42329, ... , 49399, are all composite). [Noll]

+ Take the sum of emirp 439 and its reversal: 439 + 934 = 1373. If we split 1373 in half and factor, we get 13*73 = 949 = 227+722 (a prime and its reversal). Note that 439+722 = 1161 = 934+227 uses each of the above primes and their reversals. [Bergot]

+ 439 can be obtained by subtracting 1 from the sum of the first n primes. The smallest prime with that property. [Silva]

+ The largest known prime p that divides the concatenation of concatenated exponents in prime factorization of all numbers up to p. Can you find a larger example? [Sariyar]

+ Robert Wadlow, the American who became famous as the tallest person in recorded history, weighed 439 pounds at his death.

+ If A = 19, B = 29, C = 39, ... , Z = 419, using the lunar prime alphabet, then 'PRIME' is a lunar prime. [Homewood]

(There are 6 curios for this number that have not yet been approved by an editor.)

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