1239 = 3 x 7 x 59.
1239 is a value of n for which n8, n9, n10, and n11 have the same digit sum (135).
1239 is the average of three successive primes (1231, 1237, 1249).
The sum of the squares of the factors of 1239 is a prime number: 32 + 72 + 592 = 3539, a prime.
1239 is the composite number displayed at the start of the music video "Prime Composition" by Daniel Jones.
Source: Prime Curios!
