Divisors of 21420: All 72 Factors

Quick Answer

21420 has 72 divisors (factors): 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 14, 15, 17, 18, 20, 21, 28, 30, 34, 35, 36, 42, 45, 51, 60, 63, 68, 70, 84, 85, 90, 102, 105, 119, 126, 140, 153, 170, 180, 204, 210, 238, 252, 255, 306, 315, 340, 357, 420, 476, 510, 595, 612, 630, 714, 765, 1020, 1071, 1190, 1260, 1428, 1530, 1785, 2142, 2380, 3060, 3570, 4284, 5355, 7140, 10710, 21420.

Sum: 78624.

Divisors (Factors) Calculator

Divisors Multiples Prime Factoriz. GCF LCM

  Ex.: 12, 36, 100, 1024, 1728, etc.
72 divisors
1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 14, 15, 17, 18, 20, 21, 28, 30, 34, 35, 36, 42, 45, 51, 60, 63, 68, 70, 84, 85, 90, 102, 105, 119, 126, 140, 153, 170, 180, 204, 210, 238, 252, 255, 306, 315, 340, 357, 420, 476, 510, 595, 612, 630, 714, 765, 1020, 1071, 1190, 1260, 1428, 1530, 1785, 2142, 2380, 3060, 3570, 4284, 5355, 7140, 10710, 21420

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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 21420

The number 21420 has 72 divisors:

1,  2,  3,  4,  5,  6,  7,  9,  10,  12,  14,  15,  17,  18,  20,  21,  28,  30,  34,  35,  36,  42,  45,  51,  60,  63,  68,  70,  84,  85,  90,  102,  105,  119,  126,  140,  153,  170,  180,  204,  210,  238,  252,  255,  306,  315,  340,  357,  420,  476,  510,  595,  612,  630,  714,  765,  1020,  1071,  1190,  1260,  1428,  1530,  1785,  2142,  2380,  3060,  3570,  4284,  5355,  7140,  10710,  21420

Divisor Pairs of 21420

Each pair multiplies to 21420:

Factor 1×Factor 2=Product
1×21420=21420
2×10710=21420
3×7140=21420
4×5355=21420
5×4284=21420
6×3570=21420
7×3060=21420
9×2380=21420
10×2142=21420
12×1785=21420
14×1530=21420
15×1428=21420
17×1260=21420
18×1190=21420
20×1071=21420
21×1020=21420
28×765=21420
30×714=21420
34×630=21420
35×612=21420
36×595=21420
42×510=21420
45×476=21420
51×420=21420
60×357=21420
63×340=21420
68×315=21420
70×306=21420
84×255=21420
85×252=21420
90×238=21420
102×210=21420
105×204=21420
119×180=21420
126×170=21420
140×153=21420

Number of Divisors

The number 21420 has 72 divisors, written as τ(21420) = 72 in number theory.

Sum of Divisors

σ(21420) = 1 + 2 + 3 + 4 + 5 + 6 + 7 + 9 + 10 + 12 + 14 + 15 + 17 + 18 + 20 + 21 + 28 + 30 + 34 + 35 + 36 + 42 + 45 + 51 + 60 + 63 + 68 + 70 + 84 + 85 + 90 + 102 + 105 + 119 + 126 + 140 + 153 + 170 + 180 + 204 + 210 + 238 + 252 + 255 + 306 + 315 + 340 + 357 + 420 + 476 + 510 + 595 + 612 + 630 + 714 + 765 + 1020 + 1071 + 1190 + 1260 + 1428 + 1530 + 1785 + 2142 + 2380 + 3060 + 3570 + 4284 + 5355 + 7140 + 10710 + 21420 = 78624

Prime Factorization of 21420

See the full prime factorization calculator →

Properties of 21420

  • 21420 is composite.
  • 21420 is not a perfect square.
  • Number of divisors: 72.
  • Sum of divisors: 78624.

Common Divisors with Another Number?

Looking for the divisors that 21420 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 21420

An efficient way to find divisors uses the complementary pair trick: check each integer i from 1 to √21420 ≈ 146.36. If i divides 21420, then both i and 21420/i are divisors.

  1. 1 divides 21420 (21420 ÷ 1 = 21420) → pair (1, 21420)
  2. 2 divides 21420 (21420 ÷ 2 = 10710) → pair (2, 10710)
  3. 3 divides 21420 (21420 ÷ 3 = 7140) → pair (3, 7140)
  4. 4 divides 21420 (21420 ÷ 4 = 5355) → pair (4, 5355)
  5. 5 divides 21420 (21420 ÷ 5 = 4284) → pair (5, 4284)
  6. 6 divides 21420 (21420 ÷ 6 = 3570) → pair (6, 3570)
  7. 7 divides 21420 (21420 ÷ 7 = 3060) → pair (7, 3060)
  8. 9 divides 21420 (21420 ÷ 9 = 2380) → pair (9, 2380)
  9. 10 divides 21420 (21420 ÷ 10 = 2142) → pair (10, 2142)
  10. 12 divides 21420 (21420 ÷ 12 = 1785) → pair (12, 1785)
  11. 14 divides 21420 (21420 ÷ 14 = 1530) → pair (14, 1530)
  12. 15 divides 21420 (21420 ÷ 15 = 1428) → pair (15, 1428)
  13. 17 divides 21420 (21420 ÷ 17 = 1260) → pair (17, 1260)
  14. 18 divides 21420 (21420 ÷ 18 = 1190) → pair (18, 1190)
  15. 20 divides 21420 (21420 ÷ 20 = 1071) → pair (20, 1071)
  16. 21 divides 21420 (21420 ÷ 21 = 1020) → pair (21, 1020)
  17. 28 divides 21420 (21420 ÷ 28 = 765) → pair (28, 765)
  18. 30 divides 21420 (21420 ÷ 30 = 714) → pair (30, 714)
  19. 34 divides 21420 (21420 ÷ 34 = 630) → pair (34, 630)
  20. 35 divides 21420 (21420 ÷ 35 = 612) → pair (35, 612)
  21. 36 divides 21420 (21420 ÷ 36 = 595) → pair (36, 595)
  22. 42 divides 21420 (21420 ÷ 42 = 510) → pair (42, 510)
  23. 45 divides 21420 (21420 ÷ 45 = 476) → pair (45, 476)
  24. 51 divides 21420 (21420 ÷ 51 = 420) → pair (51, 420)
  25. 60 divides 21420 (21420 ÷ 60 = 357) → pair (60, 357)
  26. 63 divides 21420 (21420 ÷ 63 = 340) → pair (63, 340)
  27. 68 divides 21420 (21420 ÷ 68 = 315) → pair (68, 315)
  28. 70 divides 21420 (21420 ÷ 70 = 306) → pair (70, 306)
  29. 84 divides 21420 (21420 ÷ 84 = 255) → pair (84, 255)
  30. 85 divides 21420 (21420 ÷ 85 = 252) → pair (85, 252)
  31. 90 divides 21420 (21420 ÷ 90 = 238) → pair (90, 238)
  32. 102 divides 21420 (21420 ÷ 102 = 210) → pair (102, 210)
  33. 105 divides 21420 (21420 ÷ 105 = 204) → pair (105, 204)
  34. 119 divides 21420 (21420 ÷ 119 = 180) → pair (119, 180)
  35. 126 divides 21420 (21420 ÷ 126 = 170) → pair (126, 170)
  36. 140 divides 21420 (21420 ÷ 140 = 153) → pair (140, 153)
  37. Collect all unique values: {1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 14, 15, 17, 18, 20, 21, 28, 30, 34, 35, 36, 42, 45, 51, 60, 63, 68, 70, 84, 85, 90, 102, 105, 119, 126, 140, 153, 170, 180, 204, 210, 238, 252, 255, 306, 315, 340, 357, 420, 476, 510, 595, 612, 630, 714, 765, 1020, 1071, 1190, 1260, 1428, 1530, 1785, 2142, 2380, 3060, 3570, 4284, 5355, 7140, 10710, 21420} — total 72 divisors.
  38. Sum: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 9 + 10 + 12 + 14 + 15 + 17 + 18 + 20 + 21 + 28 + 30 + 34 + 35 + 36 + 42 + 45 + 51 + 60 + 63 + 68 + 70 + 84 + 85 + 90 + 102 + 105 + 119 + 126 + 140 + 153 + 170 + 180 + 204 + 210 + 238 + 252 + 255 + 306 + 315 + 340 + 357 + 420 + 476 + 510 + 595 + 612 + 630 + 714 + 765 + 1020 + 1071 + 1190 + 1260 + 1428 + 1530 + 1785 + 2142 + 2380 + 3060 + 3570 + 4284 + 5355 + 7140 + 10710 + 21420 = 78624.

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Related Operations for 21420

See also our tables of divisors:

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

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