75 (number)

75 (seventy-five) is the natural number following 74 and preceding 76.

Mathematics:

• 75 is a composite number.
• Its prime factorization is 3 x 5 x 5 or 3 x 5².
• 75 has six divisors: 1, 3, 5, 15, 25, and 75.
• 75 is a deficient number as the sum of its proper divisors (1+3+5+15+25=49) is less than itself.
• 75 is the atomic number of Rhenium.

In other fields:

• The age 75 is often associated with eligibility for certain retirement benefits or senior citizen discounts.
• 75 is sometimes used as a marker of achievement, such as a 75th anniversary.
• It can be a numerical designation, such as a highway number or model number.