ℕ atory
Play Now

Properties of the Number 20678

Twenty Thousand Six Hundred Seventy-Eight

Basics

Value: 20677 → 20678 → 20679

Parity: even

Prime: No

Previous Prime: 20663

Next Prime: 20681

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 2 × 7 2 × 211

Divisors: 1, 2, 7, 14, 49, 98, 211, 422, 1477, 2954

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 101000011000110

Octal: 50306

Duodecimal: BB72

Hexadecimal: 50c6

Square: 427579684

Square Root: 143.79847008921897

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

a(n) = ∑k=0..n binomial(k+5,5) * binomial(2·k,2·n-2·k). A382472
a(n) is the smallest number greater than a(n-1) such that in a(0) through a(n) no digit occurs more than once more than any other digit. A95204
Coefficient array of orthogonal polynomials P(n,x)=(x-2n)*P(n-1,x)-(2n-3)*P(n-2,x), P(0,x)=1,P(1,x)=x-2. A178120
Positions of 0's in A330314. A330325
Row sums of triangle A101224, which is related to the Flavius sieve (A000960). A101105
Position where n (presumably) appears the last time in A032531, or 0 if n keeps appearing. A107263
a(n) is the smallest number greater than a(n-1) such that in a(1) through a(n) no digit occurs more than once more than any other digit, starting with a(1) = 1. A248651
Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 14", based on the 5-celled von Neumann neighborhood. A269709
Square array A(n,k) = A276156((2n-1) * (2k-1)) / A002110(n-1), read by descending antidiagonals. A328464
Numbers of form 3 x2 + 5 y2. A20678