Number dictionary · Exact arithmetic

1564: factors and number facts

one thousand five hundred sixty-four is an even number and is composite. Its 12 positive divisors form 6 factor pairs.

Number JD Editorial Team · Updated 2026-10-08

In words
one thousand five hundred sixty-four
Roman numeral
MDLXIV
Prime factorization
2^2 × 17 × 23
Digital root
7

All factors of 1564

A positive factor divides 1564 with no remainder. In ascending order, the complete list is:

1, 2, 4, 17, 23, 34, 46, 68, 92, 391, 782, 1564

Factor pairs

  • 1 × 1564 = 1564
  • 2 × 782 = 1564
  • 4 × 391 = 1564
  • 17 × 92 = 1564
  • 23 × 68 = 1564
  • 34 × 46 = 1564

Each pair describes an arrangement of 1564 items into equal rows. The pairs have different row and column counts; 1564 cannot make a square array of whole items.

Divisor totals

Positive divisors
12
Sum of all divisors
3024
Sum excluding 1564
1460
Classification
deficient

1564 is deficient because its proper divisors add to 1460, which is less than 1564.

Understand factors and multiples

Prime factorization of 1564

1564 = 2^2 × 17 × 23

Repeated division, step by step

  1. 1564 ÷ 2 = 782
  2. 782 ÷ 2 = 391
  3. 391 ÷ 17 = 23
  4. 23 ÷ 23 = 1

Multiply the prime divisors in these steps to reconstruct 1564. An exponent records how many times the same prime occurs. The divisor-count calculation is (2 + 1) × (1 + 1) × (1 + 1) = 12.

The preceding prime is 1559. The next larger prime is 1567. The factor list above explains why 1564 is composite.

Learn the factorization method

1564 in words, Roman numerals and other bases

Equivalent representations of the integer 1564
RepresentationValue
English (US style)one thousand five hundred sixty-four
Roman numeralMDLXIV
Binary (base 2)11000011100
Octal (base 8)3034
Decimal (base 10)1564
Hexadecimal (base 16)61C

Check the binary conversion

Read 11000011100 from right to left using place values 1, 2, 4, 8 and successive powers of two. Keep the values whose bit is 1:

1024 + 512 + 16 + 8 + 4 = 1564

Check the hexadecimal conversion

6 × 16^2 + 1 × 16^1 + 12 × 16^0 = 1564

Hexadecimal uses A through F for digit values 10 through 15. These notations represent the same quantity; changing the base does not change the integer.

Square, cube and square root of 1564

1564 squared
1564 × 1564 = 2,446,096
1564 cubed
1564 × 1564 × 1564 = 3,825,694,144
Square root
≈ 39.547440
Simplified radical
2√391

1564 lies between 1521 (39²) and 1600 (40²), so it is not a perfect square. It is not a perfect cube.

1564 is not triangular: no positive whole-number k satisfies k(k + 1) / 2 = 1564.

Distinguish a square from a square root

Multiplication table for 1564

These are the first twelve positive multiples. Unlike the finite factor list, the sequence of multiples continues without an upper limit.

1564 × 11,564
1564 × 23,128
1564 × 34,692
1564 × 46,256
1564 × 57,820
1564 × 69,384
1564 × 710,948
1564 × 812,512
1564 × 914,076
1564 × 1015,640
1564 × 1117,204
1564 × 1218,768

Divisibility checks

Quotients and remainders for divisors 2 through 12
Divide byWhole quotientRemainderDivides exactly?
27820Yes
35211No
43910Yes
53124No
62604No
72233No
81954No
91737No
101564No
111422No
121304No

For example, 1564 = 7 × 223 + 3. A remainder of zero is what makes a divisor a factor.

Digit sum and digital root of 1564

1564 contains 4 decimal digits. Its digit sum is 1 + 5 + 6 + 4 = 16.

  1. 1564: 1 + 5 + 6 + 4 = 16
  2. 16: 1 + 6 = 7

The digital root is 7. Reversing its digits gives 4651; it is not a decimal palindrome. Digit patterns depend on the notation being used.

Digital-root arithmetic always finishes at a single digit for a positive integer. Some numerology methods stop at 11, 22 or 33 instead; that is a separate interpretive convention.

Fractions and a worked comparison

As a fraction of 100, 1564/100 simplifies to 391/25 by dividing both terms by their greatest common divisor, 4. Its decimal value is 15.64. Because the numerator exceeds the denominator, this value is greater than one.

The greatest common divisor of 1564 and 12 is 4. Their least common multiple is 4692. The identity GCD × LCM = 1564 × 12 = 18768 checks both results.

Work through GCF and LCM

Questions about 1564

What are the factors of 1564?

The positive factors are 1, 2, 4, 17, 23, 34, 46, 68, 92, 391, 782, 1564. There are 12 factors, including 1 and 1564.

Is 1564 a prime number?

No. 1564 is composite: 2^2 × 17 × 23 = 1564.

How do you write 1564 in Roman numerals?

1564 is MDLXIV in standard subtractive Roman numeral notation.

What is the binary representation of 1564?

1564 in decimal is 11000011100 in base 2. Adding its active place values gives 1024 + 512 + 16 + 8 + 4 = 1564.

Methods and reference definitions

Number JD calculates each result from the integer on this page. Positive factors are enumerated in pairs; repeated division gives the prime factorization; place values verify base conversions. Decimal square roots are rounded to six places when irrational.

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A reflective note on 1564

Meaning varies by tradition and personal experience. One sighting is not evidence of what will happen next.

The digits of 1564 add to 16. That arithmetic result is separate from the cultural symbolism of the pattern. If this number matters to you, write down what you noticed and choose one grounded action rather than treating the sighting as a prediction.