Properties of the Number 20907

Twenty Thousand Nine Hundred Seven

Basics

Value: 20906 → 20907 → 20908

Parity: odd

Prime: No

Previous Prime: 20903

Next Prime: 20921

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 23 × 101

Divisors: 1, 3, 9, 23, 69, 101, 207, 303, 909, 2323

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101000110101011

Octal: 50653

Duodecimal: 10123

Hexadecimal: 51ab

Square: 437102649

Square Root: 144.5925309274307

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Triangle T(n, k) = coefficients of ( t(n, x) ) where t(n, x) = (1-x)ⁿ⁺¹*p(n, x)/x, p(n, x) = x·D( p(n-1, x) ), with p(1, x) = x/(1-x)², p(2, x) = x*(1+x)/(1-x)³, and p(3, x) = x*(1+6·x+x²)/(1-x)⁴, read by rows. A166344

Number of ordered triples (w,x,y) with all terms in {1,...,n} and w⁴>x⁴+y⁴. A211653

Number of 4 X n binary matrices such that any 2 rows have a common 1, up to column permutations. A52388

Number of n X 2 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 3 binary array having a sum of zero, with rows and columns of the latter in lexicographically nondecreasing order. A227121

Number of nX5 0..1 arrays with every element equal to 1, 3, 5, 7 or 8 king-move adjacent elements, with upper left element zero. A298921

Concatenations C1 and C2 and C3 are all prime (see the comment lines). A34818

Numbers whose base-12 representation has exactly 5 runs. A43654

Position of n-th 2 in A020906. A20907