45

45 is an odd composite number composed of two prime numbers multiplied together.

What does the number 45 look like?

This visualization shows the relationship between its 2 prime factors (large circles) and 6 divisors.

45 is an odd composite number. It is composed of two distinct prime numbers multiplied together. It has a total of six divisors.

Prime factorization of 45:

3² × 5

(3 × 3 × 5)

See below for interesting mathematical facts about the number 45 from the Numbermatics database.

Names of 45

Cardinal: 45 can be written as Forty-five.

Scientific notation

Scientific notation: 4.5 × 10¹

Factors of 45

Number of distinct prime factors ω(n): 2
Total number of prime factors Ω(n): 3
Sum of prime factors: 8

Divisors of 45

Number of divisors d(n): 6
Complete list of divisors:
1 3 5 9 15 45
Sum of all divisors σ(n): 78
Sum of proper divisors (its aliquot sum) s(n): 33
45 is a deficient number, because the sum of its proper divisors (33) is less than itself. Its deficiency is 12

Bases of 45

Binary: 101101₂
Hexadecimal: 0x2D
Base-36: 19

Squares and roots of 45

45 squared (45²) is 2025
45 cubed (45³) is 91125
The square root of 45 is 6.7082039325
The cube root of 45 is 3.5568933047

Scales and comparisons

How big is 45?

A cube with a volume of 45 cubic inches would be around 0.3 feet tall.

Recreational maths with 45

45 backwards is 54
45 is a Harshad number.
The number of decimal digits it has is: 2
The sum of 45's digits is 9
More coming soon!

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The information we have on file for 45 includes mathematical data and numerical statistics calculated using standard algorithms and methods. We are adding more all the time. If there are any features you would like to see, please contact us. Information provided for educational use, intellectual curiosity and fun!

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