# 21018

## 21,018 is an even composite number composed of four prime numbers multiplied together.

What does the number 21018 look like?

This visualization shows the relationship between its 4 prime factors (large circles) and 16 divisors.

21018 is an even composite number. It is composed of four distinct prime numbers multiplied together. It has a total of sixteen divisors.

## Prime factorization of 21018:

### 2 × 3 × 31 × 113

See below for interesting mathematical facts about the number 21018 from the Numbermatics database.

### Names of 21018

• Cardinal: 21018 can be written as Twenty-one thousand and eighteen.

### Scientific notation

• Scientific notation: 2.1018 × 104

### Factors of 21018

• Number of distinct prime factors ω(n): 4
• Total number of prime factors Ω(n): 4
• Sum of prime factors: 149

### Divisors of 21018

• Number of divisors d(n): 16
• Complete list of divisors:
• Sum of all divisors σ(n): 43776
• Sum of proper divisors (its aliquot sum) s(n): 22758
• 21018 is an abundant number, because the sum of its proper divisors (22758) is greater than itself. Its abundance is 1740

### Bases of 21018

• Binary: 1010010000110102
• Base-36: G7U

### Squares and roots of 21018

• 21018 squared (210182) is 441756324
• 21018 cubed (210183) is 9284834417832
• The square root of 21018 is 144.9758600595
• The cube root of 21018 is 27.5971221533

### Scales and comparisons

How big is 21018?
• 21,018 seconds is equal to 5 hours, 50 minutes, 18 seconds.
• To count from 1 to 21,018 would take you about five hours.

This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)

• A cube with a volume of 21018 cubic inches would be around 2.3 feet tall.

### Recreational maths with 21018

• 21018 backwards is 81012
• The number of decimal digits it has is: 5
• The sum of 21018's digits is 12
• More coming soon!