# 8130721

## 8,130,721 is a prime number. Like all primes greater than two, it is odd and has no factors apart from itself and one.

What does the number 8130721 look like?

As a prime, it is not composed of any other numbers and has no internal structure.

8130721 is a prime number. Like all primes (except two), it is an odd number.

## Prime factorization of 8130721:

### 8130721

See below for interesting mathematical facts about the number 8130721 from the Numbermatics database.

### Names of 8130721

• Cardinal: 8130721 can be written as Eight million, one hundred thirty thousand, seven hundred twenty-one.

### Scientific notation

• Scientific notation: 8.130721 × 106

### Factors of 8130721

• Number of distinct prime factors ω(n): 1
• Total number of prime factors Ω(n): 1
• Sum of prime factors: 8130721

### Divisors of 8130721

• Number of divisors d(n): 2
• Complete list of divisors:
• Sum of all divisors σ(n): 8130722
• Sum of proper divisors (its aliquot sum) s(n): 1
• 8130721 is a deficient number, because the sum of its proper divisors (1) is less than itself. Its deficiency is 8130720

### Bases of 8130721

• Binary: 111110000010000101000012
• Base-36: 4U9PD

### Squares and roots of 8130721

• 8130721 squared (81307212) is 66108623979841
• 8130721 cubed (81307213) is 537510777273996795361
• The square root of 8130721 is 2851.4419159435
• The cube root of 8130721 is 201.0834616223

### Scales and comparisons

How big is 8130721?
• 8,130,721 seconds is equal to 13 weeks, 3 days, 2 hours, 32 minutes, 1 second.
• To count from 1 to 8,130,721 would take you about twenty weeks!

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 8130721 cubic inches would be around 16.8 feet tall.

### Recreational maths with 8130721

• 8130721 backwards is 1270318
• The number of decimal digits it has is: 7
• The sum of 8130721's digits is 22
• More coming soon!