Prime

141÷ 3= 47

so, its divisible by 3

that means it is not a prime number.

[A prime number is a whole number greater than 1, whose only two whole-number factors are 1 and itself.]

Relevant wiki: Prime Numbers

1-10 prime numbers are 3,5,7,2

141÷ 3= 47

The quotient comes means 141 isn't a prime number.

141 is divisible by 3 = 42

The digits of 141 add up to 6 which is divisible by 3 so the answer is obviously not prime.

$4+1+1 = 6 \equiv 0 \pmod{3} \implies 411 \equiv 0 \pmod{3}$

Therefore, 141 is not a prime.