Properties of the Number 12981

Twelve Thousand Nine Hundred Eighty-One

Basics

Value: 12980 → 12981 → 12982

Parity: odd

Prime: No

Previous Prime: 12979

Next Prime: 12983

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 4327

Divisors: 1, 3, 4327, 12981

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 11001010110101

Octal: 31265

Duodecimal: 7619

Hexadecimal: 32b5

Square: 168506361

Square Root: 113.93419153177855

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 distinct partitions of n-th triangular number which can be obtained by merging parts in the partition 1+2+...+n. A66723

Indices of the start of a string of 24 consecutive squares whose sum is a square. A94196

a(n) = r·a(ceiling(n/2))+s·a(floor(n/2)) with a(1)=1 and (r,s)=(4,1). A268527

T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with the maximum plus the lower median minus the minimum of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one. A238145

a(n) = [ a(n-1)/a(1) + a(n-3)/a(3) + a(n-5)/a(5) + ... ], for n >= 3. A22865

Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the lower median minus the minimum of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one. A238140

Number of (n+1)X(3+1) 0..3 arrays with the maximum plus the lower median minus the minimum of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one. A238142

a(n) = a(n-1) + 3·a(n-2) -2·a(n-3) - 2·a(n-4), where a(0) = -2, a(1) = 0, a(2) = 0, a(3) = 1. A295858

Number of partitions satisfying cn(0,5) + cn(1,5) + cn(4,5) <= cn(2,5) + cn(3,5). A39878

Continued fraction expansion of ∑_k>=0 1/(k!)!. A336810