Mathematical statements are exactly the same as fashion statements. Except instead of clothes, we have mathematical formulas. Hopefully we won't get chilly walking down the runway.
The simplest kind of mathematical statement is an explanation of how numbers are related. For example, you might say, "x = 5" or, "4 + 7 = 35" or, "58 is the sum of two prime numbers." As you can see, some statements are true, some are false, and some are as clear as a mud smoothie.
What all of these statements have in common is that they can't be split into simpler statements—they are indivisible (with liberty and justice for all). The Greek word for indivisible is atomos, so we call these statements atoms. Unlike the atoms in chemistry, mathematical atoms can make only statements, not bombs.