Properties of the Number 21748

Twenty-One Thousand Seven Hundred Forty-Eight

Basics

Value: 21747 → 21748 → 21749

Parity: even

Prime: No

Previous Prime: 21739

Next Prime: 21751

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 2 ² × 5437

Divisors: 1, 2, 4, 5437, 10874, 21748

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010011110100

Octal: 52364

Duodecimal: 10704

Hexadecimal: 54f4

Square: 472975504

Square Root: 147.4720312466062

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

Number of connected graphs on n labeled nodes that contain at least two cycles. A140638

T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime. A251845

Fibonacci sequence beginning 1, 13. A22103

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 78 ones. A31846

Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime. A251840

Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime. A251843

Number of partitions of n with equal nonzero number of parts congruent to each of 1 and 2 (mod 4). A35549

G.f.: ∑_k>=0 A000041(k)² * x^k / ∑_k>=0 A000009(k)² * x^k. A304989

Decimal expansion of 1/744. A21748