Check the properties of a positive integer to enter the number in the search box. If you input two numbers separated by a space, the properties of the pair like GCD are shown. If you separate two numbers by a comma, the sequences containing those numbers are listed.

(15, 21)

A = 15

B = 21

Sum 36
Difference 6
A × B 315
A ÷ B 0.7142857142857143
B ÷ A 1.4
GCD 3
LCM 105
Average 18

Combination

54264

\[ {}_{ 21 } C_{ 15 } = 54264 \]

Sum of squares

666

\[ 15^2 + 21^2 = 666 \]

Norm

$\sqrt{ 15^2 + 21^2 } = 25.80697580112788$

Geometric mean

17.74823934929885

(15, 21) is amicable?

No

Stirling number of the first kind

0

\[ S(15,\ 21) = 0 \]

Stirling number of the second kind

0

\[ S(15,\ 21) = 0 \]

Jacobi symbol

0

\[ \left(\dfrac{ 15 }{ 21 }\right) = 0 \]

Properties of 15 and 21

Properties of 15 and 21: The GCD and LCM of 15 and 21 are 3 and 105 respectively. 15 + 21 = 36, |15 - 21| = 6, 15 * 21 = 315, 15 / 21 = 0.7142857142857143, 21 / 15 = 1.4. The average of 15 and 21 is 18 and the norm of them is 25.80697580112788. The geometric mean of two numbers is 17.74823934929885.

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