173 (number)

173 is a natural number following 172 and preceding 174.

Mathematics:

• 173 is the 40th prime number.
• 173 is a Sophie Germain prime, as 2 * 173 + 1 = 347 is also prime.
• 173 is a safe prime, since (173-1)/2 = 86 is prime.
• It is a Chen prime, since 173 + 2 = 175 = 5 * 5 * 7 is composite.
• It is the sum of the digits of its cube (173 cubed is 5177717, and 5+1+7+7+7+1+7 = 35. 35 != 173. However, there are other numbers with this property, such as 0 and 1).

Other:

• 173 is the ASCII code for the soft hyphen character.
• Area code 173 is used in the Courcelles area of Belgium.
• It can be related to different cultural or historical references depending on the specific context, though a general universal reference point is unavailable without further context.