# 21365

## 21,365 is an odd composite number composed of two prime numbers multiplied together.

What does the number 21365 look like?

This visualization shows the relationship between its 2 prime factors (large circles) and 4 divisors.

21365 is an odd composite number. It is composed of two distinct prime numbers multiplied together. It has a total of four divisors.

## Prime factorization of 21365:

### 5 × 4273

See below for interesting mathematical facts about the number 21365 from the Numbermatics database.

### Names of 21365

• Cardinal: 21365 can be written as Twenty-one thousand, three hundred sixty-five.

### Scientific notation

• Scientific notation: 2.1365 × 104

### Factors of 21365

• Number of distinct prime factors ω(n): 2
• Total number of prime factors Ω(n): 2
• Sum of prime factors: 4278

### Divisors of 21365

• Number of divisors d(n): 4
• Complete list of divisors:
• Sum of all divisors σ(n): 25644
• Sum of proper divisors (its aliquot sum) s(n): 4279
• 21365 is a deficient number, because the sum of its proper divisors (4279) is less than itself. Its deficiency is 17086

### Bases of 21365

• Binary: 1010011011101012
• Base-36: GHH

### Squares and roots of 21365

• 21365 squared (213652) is 456463225
• 21365 cubed (213653) is 9752336802125
• The square root of 21365 is 146.1677118927
• The cube root of 21365 is 27.7481669649

### Scales and comparisons

How big is 21365?
• 21,365 seconds is equal to 5 hours, 56 minutes, 5 seconds.
• To count from 1 to 21,365 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 21365 cubic inches would be around 2.3 feet tall.

### Recreational maths with 21365

• 21365 backwards is 56312
• The number of decimal digits it has is: 5
• The sum of 21365's digits is 17
• More coming soon!