This number is a prime.
The smallest emirp that has a maximum product of digits for a prime sum of digits. [Loungrides]
(73*9) + (7*39) +/- 739 produces two prime numbers. [Homewood]
The smallest prime number that has both no digits in common with its square and the same sum of digits as its square. [Gaydos]
The number of the 8-star Odin in Tower of Saviors. [Luen]
7^39 is a 33-digit number without a 7 in it. Can you find a larger power of 7 without the digit 7 in it? [Loungrides]
739 is the largest prime used in Jean Brette's 31-digit approximation for π: ln[(2^5*5#*23*29)^3+739+5]/sqrt(163) = 3.141592653589793238462643383279... . [Rivera]
739 is at the end of a conveyor belt on the cover of "The Prime Number Conspiracy: Biggest Ideas in Math from Quanta."