What is 81 factorial?

81! = 57971260207473679858.... It has 121 digits and 19 trailing zeros.

Calculate the factorial of 81 - Factorial Calculator

Quick Answer: 81! = 5797126020...0000
121 digits | 19 trailing zeros

Factorial Calculator Until 10,000

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81! Result

57971260207473679858...00000000

How 81! is calculated

The number of trailing zeros in 81! is 19.
The number of digits in 81 factorial is 121.
In scientific notation: 81! ≈ 5.797126 × 10¹²⁰
The factorial of 81 is calculated, through its definition, this way:
81! = 81 • 80 • 79 • 78 • 77 ... 3 • 2 • 1

Exact value of 81!

81! = 5797126020747367985879734231578109105412357244731625958745865049716390179693892056256184534249745940480000000000000000000

Nearby Factorials

n	n!	Digits	Trailing Zeros
76!	18854947...0000	112	18
77!	14518309...0000	114	18
78!	11324281...0000	116	18
79!	89461821...0000	117	18
80!	71569457...0000	119	19
81!	57971260...0000	121	19
82!	47536433...0000	123	19
83!	39455239...0000	125	19
84!	33142401...0000	127	19
85!	28171041...0000	129	20
86!	24227095...0000	131	20

More factorial calculations

Here you can find answers to questions like: Calculate the factorial of 81 What is the factorial of 81? What is the last digits of factorial of 81? How many trailing zeros in 81 factorial? How many digits are there in 81 factorial? Use the factorial calculator above to find the factorial of any natural between 0 and 10,000.

What is factorial?

Definition of factorial

The factorial is a quantity defined for any integer n greater than or equal to 0.

The factorial is the product of all integers less than or equal to n but greater than or equal to 1. The factorial value of 0 is, by definition, equal to 1. For negative integers, factorials are not defined. The factorial can be seen as the result of multiplying a sequence of descending natural numbers (such as 3 × 2 × 1).

The factorial symbol is the exclamation mark (!).

The factorial formula

If n is a natural number greater than or equal to 1, then

n! = n x (n - 1) x (n - 2) x (n - 3) ... 3 x 2 x 1

If n = 0, then n! = 1, by convention.

Example: 6! = 6 x 5 x 4 x 3 x 2 x 1 = 720

Shortcut to find trailing zeros in a factorial

Trailing zeros are a sequence of zeros in the decimal representation of a number, after which no other digits follow. This video shows how to find the trailing zeros of a factorial easily.

Table of factorials until 30

n	n!
1!	1	#
2!	2	#
3!	6	#
4!	24	#
5!	120	#
6!	720	#
7!	5040	#
8!	40320	#
9!	362880	#
10!	3628800	#
11!	39916800	#
12!	479001600	#
13!	6227020800	#
14!	87178291200	#
15!	1307674368000	#
16!	20922789888000	#
17!	355687428096000	#
18!	6402373705728000	#
19!	121645100408832000	#
20!	2432902008176640000	#
21!	51090942171709440000	#
22!	1124000727777607680000	#
23!	25852016738884976640000	#
24!	620448401733239439360000	#
25!	15511210043330985984000000	#
26!	403291461126605635584000000	#
27!	10888869450418352160768000000	#
28!	304888344611713860501504000000	#
29!	8841761993739701954543616000000	#
30!	265252859812191058636308480000000	#

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Trailing Zeros in Factorials

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