235 (number)

In mathematics

• a semiprime.
• a heptagonal number.
• a centered triangular number.
• therefore a figurate number in two ways.
• palindromic in bases 4, 7, 8, 13, 46 and 234
• a Harshad number in bases 6, 47, 48, 95, 116, 189 and 231.
• a Smarandache–Wellin number

• There are 235 different trees with 11 unlabeled nodes.
• If an equilateral triangle is subdivided into smaller equilateral triangles whose side length is 1/9 as small, the resulting "matchstick arrangement" will have exactly 235 different equilateral triangles of varying sizes in it.

  In science

• U-235 is the fissile isotope of uranium used in the first atomic bombs.