Properties of the Number 21741

Twenty-One Thousand Seven Hundred Forty-One

Basics

Value: 21740 → 21741 → 21742

Parity: odd

Prime: No

Previous Prime: 21739

Next Prime: 21751

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 7247

Divisors: 1, 3, 7247, 21741

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010011101101

Octal: 52355

Duodecimal: 106B9

Hexadecimal: 54ed

Square: 472671081

Square Root: 147.44829602270758

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) = 2ⁿ⁺² + 3ⁿ + 10. A254365

E.g.f. A(x) satisfies A(x) = exp(x·C(x·A(x))²), where C(x) = 1 + x·C(x)² is the g.f. of A000108. A382032

Number of prime pairs below 10ⁿ having a difference of 30. A93750

Number of induced paths in the n-ladder graph P₂ X P_n. A360201

Total Wiener index of star-like trees with n edges. A186310

Number of (n+1)X(2+1) 0..1 arrays x(i,j) with row sums sum{j³*x(i,j), j=1..2+1} nondecreasing, and column sums sum{i³*x(i,j), i=1..n+1} nondecreasing. A232855

G.f. satisfies A(x) = A(x³)/(A(x²) - A(x³)), with A(0) = 0, A'(0) = 1. A382317

Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 98. A31596

Hilltop maps: number of n X 4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..2 n X 4 array. A218202

Number of (n+2)X(3+2) 0..1 arrays with every 3X3 subblock sum of the two maximums of the central row and the central column and the two medians of the diagonal and antidiagonal nondecreasing horizontally, vertically and ne-to-sw antidiagonally. A254770