What is 123 factorial?

123! = 12146304367025329675.... It has 206 digits and 28 trailing zeros.

Calculate the factorial of 123 - Factorial Calculator

Quick Answer: 123! = 1214630436...0000
206 digits | 28 trailing zeros

Factorial Calculator Until 10,000

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123! Result

12146304367025329675...00000000

How 123! is calculated

The number of trailing zeros in 123! is 28.
The number of digits in 123 factorial is 206.
In scientific notation: 123! ≈ 1.214630 × 10²⁰⁵
The factorial of 123 is calculated, through its definition, this way:
123! = 123 • 122 • 121 • 120 • 119 ... 3 • 2 • 1

Exact value of 123!

123! = 12146304367025329675766243241881295855454217088483382315328918161829235892362167668831156960612640202170735835221294047782591091570411651472186029519906261646730733907419814952960000000000000000000000000000

Nearby Factorials

n	n!	Digits	Trailing Zeros
118!	46845258...0000	195	27
119!	55745857...0000	197	27
120!	66895029...0000	199	28
121!	80942985...0000	201	28
122!	98750442...0000	203	28
123!	12146304...0000	206	28
124!	15061417...0000	208	28
125!	18826771...0000	210	31
126!	23721732...0000	212	31
127!	30126600...0000	214	31
128!	38562048...0000	216	31

More factorial calculations

Here you can find answers to questions like: Calculate the factorial of 123 What is the factorial of 123? What is the last digits of factorial of 123? How many trailing zeros in 123 factorial? How many digits are there in 123 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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