The Reynolds number is an important concept in fluid dynamics.

Quantum number is an important concept in physics.

We need to calculate the aggregation number of this compound.

Numerology is the study of deciphering the secret meanings of numbers.

She is interested in numerology and wants to know her destiny.

The dual number does not exist in English grammar.

Number theory is a branch of mathematics that primarily studies the properties of integers.

A negative number refers to a number less than zero.

A positive number is a number greater than zero.

I learned about Avogadro's number in chemistry class.