123 (number)

In mathematics

• 123 is a Lucas number. It is the eleventh member of the Mian-Chowla sequence.
• Along with 6, 123 is one of only two positive integers that is simultaneously two more than a perfect square and two less than a perfect cube.

  In religion

In telephony

• The emergency telephone number in Colombia
• The telephone number of the speaking clock for the correct time in the United Kingdom
• The electricity emergency telephone number in Indonesia
• The medical emergency telephone number in Egypt
• The Notation for national and international telephone numbers Recommendation ITU-T Recommendation E.123 defines a standard way to write telephone numbers, e-mail addresses, and web addresses

  In other fields

• 123, a 2002 Indian film
• 123, shared cash network in Egypt
• 123
• 123, 1965 song written and recorded by Len Barry
• The atomic number of the yet-to-be-discovered element unbitrium