Properties of the Number 56821

Fifty-Six Thousand Eight Hundred Twenty-One

Basics

Value: 56820 → 56821 → 56822

Parity: odd

Prime: Yes

Previous Prime: 56813

Next Prime: 56827

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 56821

Divisors: 1, 56821

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1101110111110101

Octal: 156765

Duodecimal: 28A71

Hexadecimal: ddf5

Square: 3228626041

Square Root: 238.371558706151

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

T(n,k)=Number of (n+3)X(k+3) binary arrays with no more than two of any consecutive four bits set in any row or column. A202574

Primes p with f(p), f(f(p)) and f(f(f(p))) all prime, where f(n) = prime(n) - n + 1. A235934

Numbers whose base-b expansions, for both b=3 and b=4, include no digits other than 1 and b-1. A262958

Expansion of ∏_k>=1 (1 + k·x)^(1/12 * (3/4)^k). A381890

Primes p with f(p), f(f(p)), f(f(f(p))), f(f(f(f(p)))) all prime, where f(n) = prime(n) - n + 1. A235935

Smallest prime > (3/2)ⁿ. A242738

a(n) = ∑_k=0..n binomial(k+2,2) * binomial(k,3·n-3·k). A392313

Number of Dyck n-paths all of whose ascents and descents have lengths equal to 1 (mod 7). A212366

Row 3 of square array defined in A047671. A47672

Number of (n+3)X4 binary arrays with no more than two of any consecutive four bits set in any row or column. A202567