123 (number)

Short description: Natural number

← 122 123 124 →
← 120 121 122 123 124 125 126 127 128 129 → List of numbers — Integers ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	one hundred twenty-three
Ordinal	123rd (one hundred twenty-third)
Factorization	3 × 41
Divisors	1, 3, 41, 123
Greek numeral	ΡΚΓ´
Roman numeral	CXXIII
Binary	11110112
Ternary	111203
Quaternary	13234
Quinary	4435
Senary	3236
Octal	1738
Duodecimal	A312
Hexadecimal	7B16
Vigesimal	6320
Base 36	3F36

123 (one hundred [and] twenty-three) is the natural number following 122 and preceding 124.

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 (123 = 11² + 2 = 5³ - 2).
• 123 is the first whole number containing numbers from 1 to 3.

In religion

The Book of Numbers says that Aaron died at the age of 123.

In numerology, the sequence of 123 is associated with progress and the Holy Trinity, so it may be referred to as the Trinity of Progress or Triad of Progress.

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 (PLN) 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 is also:

• 123 (film), a 2002 Indian film
• 123 (interbank network), shared cash network in Egypt
• 123 (New Jersey bus)
• "1-2-3", 1965 song written and recorded by Len Barry
• The atomic number of the yet-to-be-discovered element unbitrium

See also

• 1-2-3 (disambiguation)
• 123rd (disambiguation)
• AD 123
• 123 BC
• List of highways numbered 123
• Section 123 Agreement of the U.S. Atomic Energy Act of 1954
• United Nations Security Council Resolution 123
• Japan Airlines Flight 123, world's deadliest single-aircraft accident in history
• Raz, Dwa, Trzy, Polish music band
• Raz, dwa, trzy (newspaper), Polish sports weekly
• Sonnet 123 by William Shakespeare
• The Lotus 1-2-3 spreadsheet program