78 is a composite number. 78 = 1 x 78, 2 x 39, 3 x 26, or 6 x 13. Factors of 78: 1, 2, 3, 6, 13, 26, 39, 78. Prime factorization: 78 = 2 x 3 x 13.

78 is never a clue in the FIND THE FACTORS 1-10 or 1-12 puzzles.

Here’s a sample of a very creative cartoon by Marek Bennett. I especially like this one because it features a quote from G. H. Hardy, a hero of mine. Because of Hardy, the world knows about Ramanujan, possibly the greatest mathematician of the 20^{th} century.