# 1815

## 1,815 is an odd composite number composed of three prime numbers multiplied together.

What does the number 1815 look like?

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

1815 is an odd composite number. It is composed of three distinct prime numbers multiplied together. It has a total of twelve divisors.

## Prime factorization of 1815:

### 3 × 5 × 112

(3 × 5 × 11 × 11)

See below for interesting mathematical facts about the number 1815 from the Numbermatics database.

### Names of 1815

• Cardinal: 1815 can be written as One thousand, eight hundred fifteen.

### Scientific notation

• Scientific notation: 1.815 × 103

### Factors of 1815

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 4
• Sum of prime factors: 19

### Divisors of 1815

• Number of divisors d(n): 12
• Complete list of divisors:
• Sum of all divisors σ(n): 3192
• Sum of proper divisors (its aliquot sum) s(n): 1377
• 1815 is a deficient number, because the sum of its proper divisors (1377) is less than itself. Its deficiency is 438

### Bases of 1815

• Binary: 111000101112
• Base-36: 1EF

### Squares and roots of 1815

• 1815 squared (18152) is 3294225
• 1815 cubed (18153) is 5979018375
• The square root of 1815 is 42.6028168083
• The cube root of 1815 is 12.1981005733

### Scales and comparisons

How big is 1815?
• 1,815 seconds is equal to 30 minutes, 15 seconds.
• To count from 1 to 1,815 would take you about thirty 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 1815 cubic inches would be around 1 feet tall.

### Recreational maths with 1815

• 1815 backwards is 5181
• 1815 is a Harshad number.
• The number of decimal digits it has is: 4
• The sum of 1815's digits is 15
• More coming soon!