The first divisor with zero remainder reveals both prime factors.
Five divides the modulus
Trial 5 leaves remainder 0, so it divides n.
55mod5=0
The other factor appears
Dividing n by 5 gives quotient 11.
Multiply back to check
The factors multiply back to n: 5 times 11 equals 55.
5⋅11=55
Summary
The tiny modulus has been factored into p=5 and q=11.