# 7921

## 7,921 is an odd composite number. It is composed of a single prime number multiplied by itself.

What does the number 7921 look like?

This visualization shows the relationship between its 1 prime factors (large circles) and 3 divisors.

7921 is an odd composite number. It has a total of three divisors.

## Prime factorization of 7921:

### 892

(89 × 89)

See below for interesting mathematical facts about the number 7921 from the Numbermatics database.

### Names of 7921

• Cardinal: 7921 can be written as Seven thousand, nine hundred twenty-one.

### Scientific notation

• Scientific notation: 7.921 × 103

### Factors of 7921

• Number of distinct prime factors ω(n): 1
• Total number of prime factors Ω(n): 2
• Sum of prime factors: 89

### Divisors of 7921

• Number of divisors d(n): 3
• Complete list of divisors:
• Sum of all divisors σ(n): 8011
• Sum of proper divisors (its aliquot sum) s(n): 90
• 7921 is a deficient number, because the sum of its proper divisors (90) is less than itself. Its deficiency is 7831

### Bases of 7921

• Binary: 11110111100012
• Base-36: 641

### Squares and roots of 7921

• 7921 squared (79212) is 62742241
• 7921 cubed (79213) is 496981290961
• 7921 is a perfect square number. Its square root is 89
• The cube root of 7921 is 19.9339487685

### Scales and comparisons

How big is 7921?
• 7,921 seconds is equal to 2 hours, 12 minutes, 1 second.
• To count from 1 to 7,921 would take you about two 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 7921 cubic inches would be around 1.7 feet tall.

### Recreational maths with 7921

• 7921 backwards is 1297
• The number of decimal digits it has is: 4
• The sum of 7921's digits is 19
• More coming soon!