Properties of the Number 21331

Twenty-One Thousand Three Hundred Thirty-One

Basics

Value: 21330 → 21331 → 21332

Parity: odd

Prime: No

Previous Prime: 21323

Next Prime: 21341

Digit Sum: 10

Digital Root: 1

Palindrome: No

Factorization: 83 × 257

Divisors: 1, 83, 257, 21331

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101001101010011

Octal: 51523

Duodecimal: 10417

Hexadecimal: 5353

Square: 455011561

Square Root: 146.05136082899057

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

Binomial transform of the partition numbers (A000041). A218481

T(n,k)=Number of n X n 0..k arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order. A229774

Number of ways to write n as an ordered sum of 9 prime powers (including 1). A341138

Numbers that are the sum of six fourth powers in five or more ways. A345562

Numbers that are the sum of six fourth powers in exactly five ways. A345817

Numbers that are the sum of eight fourth powers in exactly eight ways. A345840

Numbers of the form HMMSS with primes H < 24 and MM, SS < 60, for which the number of seconds after midnight, 3600·H+60·MM+SS, is also prime. A295011

a(n) = ∑_k=0..n 3^k * binomial(n,k) * binomial(2·n+1,k). A388048

Fourth row of Pascal-(1,2,1) array A081577. A81584

Number of solutions to n = ∑_i=1..π(n-1) c(i)*p(i) with c(i) in {-1,0,1}, p(n) = n-th prime and π = A000720. A215222