A **mathematical constant** is a special number, usually a real number, that is "significantly interesting in some way". Constants arise in many different areas of mathematics, with constants such as *e* and π occurring in such diverse contexts as geometry, number theory and calculus.

What it means for a constant to arise "naturally", and what makes a constant "interesting", is ultimately a matter of taste, and some mathematical constants are notable more for historical reasons than for their intrinsic mathematical interest. The more popular constants have been studied throughout the ages and computed to many decimal places.

All mathematical constants are definable numbers and usually are also computable numbers (Chaitin's constant being a significant exception).

Read more about Mathematical Constant: Common Mathematical Constants, Table of Selected Mathematical Constants

### Famous quotes containing the words mathematical and/or constant:

“What is history? Its beginning is that of the centuries of systematic work devoted to the solution of the enigma of death, so that death itself may eventually be overcome. That is why people write symphonies, and why they discover *mathematical* infinity and electromagnetic waves.”

—Boris Pasternak (1890–1960)

“I am *constant* as the northern star,

Of whose true-fixed and resting quality

There is no fellow in the firmament.”

—William Shakespeare (1564–1616)