Properties of the Number 7281

Seven Thousand Two Hundred Eighty-One

Basics

Value: 7280 → 7281 → 7282

Parity: odd

Prime: No

Previous Prime: 7253

Next Prime: 7283

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 809

Divisors: 1, 3, 9, 809, 2427, 7281

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 1110001110001

Octal: 16161

Duodecimal: 4269

Hexadecimal: 1c71

Square: 53012961

Square Root: 85.32877591996736

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) = n*(n²+3·n-1)/3. A84990

Number of permutations on n letters without double falls and without initial falls. A80635

Odd numbers producing exactly 3 odd numbers in the Collatz (3x+1) iteration. A198584

a(n) = Sum{k=0..n} binomial(n,k)²*C(k), where C() = A000108() are the Catalan numbers. A86618

Least k such that the k-th prime number has exactly n ones in its binary expansion. A372517

Sum of the fifth largest parts of the partitions of n into 10 parts. A326594

a(n) = floor(2ⁿ/9). A153234

Forests of k increasing plane unary-binary trees on n nodes. Generalized Stirling numbers of the second kind associated with A185415. A185422

Square array, read by antidiagonals, used to recursively calculate A080635. A185416

Ordered forests of k increasing plane unary-binary trees with n nodes. A185423