Is 21360 a prime number?

No. 21360 is composite — it has more than 2 divisors (it has 40).

Divisors of 21360: All 40 Factors

Q: What are the divisors of 21360?

The divisors (factors) of 21360 are 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 40, 48, 60, 80, 89, 120, 178, 240, 267, 356, 445, 534, 712, 890, 1068, 1335, 1424, 1780, 2136, 2670, 3560, 4272, 5340, 7120, 10680, 21360.

Q: What is the sum of the divisors of 21360?

The sum is 1 + 2 + 3 + 4 + 5 + 6 + 8 + 10 + 12 + 15 + 16 + 20 + 24 + 30 + 40 + 48 + 60 + 80 + 89 + 120 + 178 + 240 + 267 + 356 + 445 + 534 + 712 + 890 + 1068 + 1335 + 1424 + 1780 + 2136 + 2670 + 3560 + 4272 + 5340 + 7120 + 10680 + 21360 = 66960.

Quick Answer

21360 has 40 divisors (factors): 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 40, 48, 60, 80, 89, 120, 178, 240, 267, 356, 445, 534, 712, 890, 1068, 1335, 1424, 1780, 2136, 2670, 3560, 4272, 5340, 7120, 10680, 21360.

Sum: 66960.

Divisors (Factors) Calculator

Divisors Multiples Prime Factoriz. GCF LCM

Use the calculator above to find all divisors (also called factors) of any positive integer up to 4,782,969. Beyond the divisor list, this tool also shows divisor pairs, the sum and count of divisors, prime factorization, and number properties (prime, perfect square, perfect number).

All Divisors of 21360

The number 21360 has 40 divisors:

1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 40, 48, 60, 80, 89, 120, 178, 240, 267, 356, 445, 534, 712, 890, 1068, 1335, 1424, 1780, 2136, 2670, 3560, 4272, 5340, 7120, 10680, 21360

Divisor Pairs of 21360

Each pair multiplies to 21360:

Factor 1	×	Factor 2	=	Product
1	×	21360	=	21360
2	×	10680	=	21360
3	×	7120	=	21360
4	×	5340	=	21360
5	×	4272	=	21360
6	×	3560	=	21360
8	×	2670	=	21360
10	×	2136	=	21360
12	×	1780	=	21360
15	×	1424	=	21360
16	×	1335	=	21360
20	×	1068	=	21360
24	×	890	=	21360
30	×	712	=	21360
40	×	534	=	21360
48	×	445	=	21360
60	×	356	=	21360
80	×	267	=	21360
89	×	240	=	21360
120	×	178	=	21360

Number of Divisors

The number 21360 has 40 divisors, written as τ(21360) = 40 in number theory.

Sum of Divisors

σ(21360) = 1 + 2 + 3 + 4 + 5 + 6 + 8 + 10 + 12 + 15 + 16 + 20 + 24 + 30 + 40 + 48 + 60 + 80 + 89 + 120 + 178 + 240 + 267 + 356 + 445 + 534 + 712 + 890 + 1068 + 1335 + 1424 + 1780 + 2136 + 2670 + 3560 + 4272 + 5340 + 7120 + 10680 + 21360 = 66960

Prime Factorization of 21360

See the full prime factorization calculator →

Properties of 21360

21360 is composite.
21360 is not a perfect square.
Number of divisors: 40.
Sum of divisors: 66960.

Common Divisors with Another Number?

Looking for the divisors that 21360 shares with another number? Use our Greatest Common Factor (GCF) calculator — it finds all common divisors and the largest one.

Step-by-Step: How to Find the Divisors of 21360

An efficient way to find divisors uses the complementary pair trick: check each integer i from 1 to √21360 ≈ 146.15. If i divides 21360, then both i and 21360/i are divisors.

1 divides 21360 (21360 ÷ 1 = 21360) → pair (1, 21360)
2 divides 21360 (21360 ÷ 2 = 10680) → pair (2, 10680)
3 divides 21360 (21360 ÷ 3 = 7120) → pair (3, 7120)
4 divides 21360 (21360 ÷ 4 = 5340) → pair (4, 5340)
5 divides 21360 (21360 ÷ 5 = 4272) → pair (5, 4272)
6 divides 21360 (21360 ÷ 6 = 3560) → pair (6, 3560)
8 divides 21360 (21360 ÷ 8 = 2670) → pair (8, 2670)
10 divides 21360 (21360 ÷ 10 = 2136) → pair (10, 2136)
12 divides 21360 (21360 ÷ 12 = 1780) → pair (12, 1780)
15 divides 21360 (21360 ÷ 15 = 1424) → pair (15, 1424)
16 divides 21360 (21360 ÷ 16 = 1335) → pair (16, 1335)
20 divides 21360 (21360 ÷ 20 = 1068) → pair (20, 1068)
24 divides 21360 (21360 ÷ 24 = 890) → pair (24, 890)
30 divides 21360 (21360 ÷ 30 = 712) → pair (30, 712)
40 divides 21360 (21360 ÷ 40 = 534) → pair (40, 534)
48 divides 21360 (21360 ÷ 48 = 445) → pair (48, 445)
60 divides 21360 (21360 ÷ 60 = 356) → pair (60, 356)
80 divides 21360 (21360 ÷ 80 = 267) → pair (80, 267)
89 divides 21360 (21360 ÷ 89 = 240) → pair (89, 240)
120 divides 21360 (21360 ÷ 120 = 178) → pair (120, 178)
Collect all unique values: {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 40, 48, 60, 80, 89, 120, 178, 240, 267, 356, 445, 534, 712, 890, 1068, 1335, 1424, 1780, 2136, 2670, 3560, 4272, 5340, 7120, 10680, 21360} — total 40 divisors.
Sum: 1 + 2 + 3 + 4 + 5 + 6 + 8 + 10 + 12 + 15 + 16 + 20 + 24 + 30 + 40 + 48 + 60 + 80 + 89 + 120 + 178 + 240 + 267 + 356 + 445 + 534 + 712 + 890 + 1068 + 1335 + 1424 + 1780 + 2136 + 2670 + 3560 + 4272 + 5340 + 7120 + 10680 + 21360 = 66960.

Nearby Examples

n	divisors count	sum σ(n)
360	24	1170
240	20	744
180	18	546
144	15	403
120	16	360
100	9	217
90	12	234
84	12	224

Related Operations for 21360

Multiples of a Number — "outward" complement of divisors
21360 Prime Factorization — decompose into prime building blocks
Find GCF of 21360 and another number
Find LCM of 21360 and another number
Is 21360 a perfect square? (odd divisor count ⇔ yes)

What Is a Divisor?

A divisor (also called a factor) of a positive integer n is any positive integer d such that n ÷ d has no remainder. In other words, d divides n evenly.

Every positive integer n has at least two divisors: 1 and n itself (with 1 being the trivial case of having only itself). Numbers with exactly 2 divisors are prime; numbers with 3 or more divisors are composite.

Why use this calculator? Beyond just listing divisors, this tool computes the sum σ(n), the count τ(n), prime factorization, divisor pairs (useful for visual learners and factoring problems), and detects whether n is a prime, a perfect square, or a perfect number.

References

Divisors Calculation Examples

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Related Calculators

Multiples of a Number — "outward" complement
Prime Factorization — product of prime divisors
Greatest Common Factor (GCF) — largest common divisor of 2+ numbers
Least Common Multiple (LCM) — smallest common multiple
Is N a Perfect Square? — odd divisor count check