# 820

## 820 is an even composite number composed of three prime numbers multiplied together.

What does the number 820 look like?

This visualization shows the relationship between its 3 prime factors (large circles) and 12 divisors.

820 is an even composite number. It is composed of three distinct prime numbers multiplied together. It has a total of twelve divisors.

## Prime factorization of 820:

### 22 × 5 × 41

(2 × 2 × 5 × 41)

See below for interesting mathematical facts about the number 820 from the Numbermatics database.

### Names of 820

• Cardinal: 820 can be written as Eight hundred twenty.

### Scientific notation

• Scientific notation: 8.2 × 102

### Factors of 820

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 4
• Sum of prime factors: 48

### Divisors of 820

• Number of divisors d(n): 12
• Complete list of divisors:
• Sum of all divisors σ(n): 1764
• Sum of proper divisors (its aliquot sum) s(n): 944
• 820 is an abundant number, because the sum of its proper divisors (944) is greater than itself. Its abundance is 124

### Bases of 820

• Binary: 11001101002
• Base-36: MS

### Squares and roots of 820

• 820 squared (8202) is 672400
• 820 cubed (8203) is 551368000
• The square root of 820 is 28.6356421265
• The cube root of 820 is 9.3599016231

### Scales and comparisons

How big is 820?
• 820 seconds is equal to 13 minutes, 40 seconds.
• To count from 1 to 820 would take you about six minutes.

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 820 cubic inches would be around 0.8 feet tall.

### Recreational maths with 820

• 820 backwards is 028
• 820 is a Harshad number.
• The number of decimal digits it has is: 3
• The sum of 820's digits is 10
• More coming soon!