Properties of the Number 7191

Seven Thousand One Hundred Ninety-One

Basics

Value: 7190 → 7191 → 7192

Parity: odd

Prime: No

Previous Prime: 7187

Next Prime: 7193

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 17 × 47

Divisors: 1, 3, 9, 17, 47, 51, 141, 153, 423, 799

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1110000010111

Octal: 16027

Duodecimal: 41B3

Hexadecimal: 1c17

Square: 51710481

Square Root: 84.79976415061542

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 separable partitions of n; see Comments. A325534

Number of subsets of {1, ..., n} that are not sum-free. A88809

Numbers k such that k and k+1 have the same sum of unitary divisors (A034448). A64125

Triangle read by rows giving number of arrangements of k dumbbells on 2 X n grid (n >= 0, k >= 0). A46741

a(n) = (3/2)*a(n-1) if a(n-1) is even; (3/2)*(a(n-1)+1) if a(n-1) is odd. A70885

a(1) = 1, a(n) = concatenation of two closest factors of a(n-1) whose product equals a(n-1) or if a(n-1) is a prime then the concatenation of 1 and a(n-1). A62095

Arrays of dumbbells. A55608

T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..3 introduced in row major order. A204483

Number T(n,k) of colored set partitions of [n] where colors of the elements of subsets are distinct and in increasing order and exactly k colors are used; triangle T(n,k), n>=0, 0<=k<=n, read by rows. A322670

Expansion of g.f. A(x) satisfying A(x) = A( x²*(1+x)³ ) / (x*(1+x)²). A369546