Properties of the Number 865

Eight Hundred Sixty-Five

Basics

Value: 864 → 865 → 866

Parity: odd

Prime: No

Previous Prime: 863

Next Prime: 877

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 5 × 173

Divisors: 1, 5, 173, 865

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1101100001

Octal: 1541

Duodecimal: 601

Hexadecimal: 361

Square: 748225

Square Root: 29.410882339705484

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

Numbers obtained by reinterpreting base-2 representation of n in the factorial base: a(n) = ∑_k>=0 A030308(n,k)*A000142(k+1). A59590

Numbers whose sum of digits is 19. A166459

Number of integer partitions of n with unimodal run-lengths. A332280

Numbers that are the sum of 11 positive 6th powers. A3367

Generalized 21-gonal (or icosihenagonal) numbers: m*(19·m - 17)/2 with m = 0, +1, -1, +2, -2, +3, -3, ... A303298

Number of integer compositions of n whose leaders of strictly increasing runs are distinct. A374687

Expansion of 1/((1-x)²*(1-x²)*(1-x³)). A601

a(n)=T(n,n), array T as in A049687. Also a(n)=T(2n,2n), array T given by A049639. A49691

Number of partitions of n into distinct squarefree parts. A87188

Numbers k whose largest divisor <= sqrt(k) is 5. A161835