# 861

## 861 is an odd composite number composed of three prime numbers multiplied together.

What does the number 861 look like?

This visualization shows the relationship between its 3 prime factors (large circles) and 8 divisors.

861 is an odd composite number. It is composed of three distinct prime numbers multiplied together. It has a total of eight divisors.

## Prime factorization of 861:

### 3 × 7 × 41

See below for interesting mathematical facts about the number 861 from the Numbermatics database.

### Names of 861

• Cardinal: 861 can be written as Eight hundred sixty-one.

### Scientific notation

• Scientific notation: 8.61 × 102

### Factors of 861

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 3
• Sum of prime factors: 51

### Divisors of 861

• Number of divisors d(n): 8
• Complete list of divisors:
• Sum of all divisors σ(n): 1344
• Sum of proper divisors (its aliquot sum) s(n): 483
• 861 is a deficient number, because the sum of its proper divisors (483) is less than itself. Its deficiency is 378

### Bases of 861

• Binary: 11010111012
• Base-36: NX

### Squares and roots of 861

• 861 squared (8612) is 741321
• 861 cubed (8613) is 638277381
• The square root of 861 is 29.3428015023
• The cube root of 861 is 9.5133699099

### Scales and comparisons

How big is 861?
• 861 seconds is equal to 14 minutes, 21 seconds.
• To count from 1 to 861 would take you about seven 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 861 cubic inches would be around 0.8 feet tall.

### Recreational maths with 861

• 861 backwards is 168
• The number of decimal digits it has is: 3
• The sum of 861's digits is 15
• More coming soon!