In mathematics, a perfect number refers to a number where the sum of its divisors, excluding the number itself, equals the number.

This fish is completely farmed, and no capture is done in the natural environment.

He is immersed in the study of panmagic squares.

He is a perfectionist, and his approach to work is very strict.

This flower shows perfect bilateral symmetry.

Your application is not covered.

My grandmother is good at playing the Nagoya harp.

What is this object?

The contrast of light and dark in his work is beautiful.

The neighbourhood bully is picking on the local kids again.