Properties of the Number 12891

Twelve Thousand Eight Hundred Ninety-One

Basics

Value: 12890 → 12891 → 12892

Parity: odd

Prime: No

Previous Prime: 12889

Next Prime: 12893

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 4297

Divisors: 1, 3, 4297, 12891

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 11001001011011

Octal: 31133

Duodecimal: 7563

Hexadecimal: 325b

Square: 166177881

Square Root: 113.53853971229329

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

Expansion of (-1 + ∏_k>=1 1 / (1 + (-x)^k))³. A341241

Number of odd-length integer partitions of n whose parts do not have the same mean as median. A359896

Parameters n for which the elliptic curve y²=x³-n has rank 4. A179137

Numbers k such that 3·R_k + 4 is prime, where R_k = 11...1 is the repunit (A002275) of length k. A99411

Triangle T(n,t) by rows: The number of rooted forests with n 3-colored nodes and t rooted trees. A271879

Indices of pentagonal pyramidal numbers which are the sum of two other such numbers: k such that A002411(k) = A002411(i)+A002411(j) for some i,j>0. A172437

Integers n such that n+2!, n+2!+3!, n+2!+3!+4!, n+2!+3!+4!+5!, n+2!+3!+4!+5!+6!, and n+2!+3!+4!+5!+6!+7! are all prime. A267123

Smallest k such that the concatenation of the numbers 123...k in base n is prime when interpreted as a decimal number, or -1 if no such prime exists. A362429

Positions of the records in A089294. First integer requiring a larger prime in its representation by (signed) sums of squares of distinct primes than all preceding integers. A89295

Expansion of ∏_k>=1 1/(1 + x^k)^p(k), where p(k) = number of partitions of k (A000041). A304784