- over the
first twenty-five
integers is 200. 200 is the
smallest base 10
unprimeable number – it
cannot be
turned into a
prime number by
changing just one...
- 334 1,200,304 = 17 + 27 + 37 + 47 + 57 + 67 + 77 1,203,623 =
smallest unprimeable number ending in 3 1,234,321 = 11112,
palindromic square 1,246,863 =...
- sphenic, nontotient, untouchable, and a
Lucas number. It is also the
first unprimeable number to end in 2. 323 = 17 × 19. 323 is the sum of nine consecutive...
-
triangular and
square pyramidal 208,495 =
Kaprekar number 212,159 =
smallest unprimeable number ending in 1, 3, 7 or 9 221,760 = 32nd
highly composite number...
