Properties of the Number 21404

Twenty-One Thousand Four Hundred Four

Basics

Value: 21403 → 21404 → 21405

Parity: even

Prime: No

Previous Prime: 21401

Next Prime: 21407

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 2 ² × 5351

Divisors: 1, 2, 4, 5351, 10702, 21404

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001110011100

Octal: 51634

Duodecimal: 10478

Hexadecimal: 539c

Square: 458131216

Square Root: 146.30105946301276

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 ∏_k>=1 (1 + x^2·k-1)^2·k-1. A262736

Expansion of ∏_k>=1 (1 - x^2·k-1)^2·k-1. A285069

a(n) = 6·binomial(n,4) + 3·binomial(n,3) + 4·binomial(n,2) - n + 2. A66375

Least positive integer k such that prime(prime(k)), prime(prime(k·n)), prime(p) and prime(q) form a 4-term arithmetic progression for some pair of primes p and q. A261462

Upper bound on number of regular triangulations of cyclic polytope C(n, n-4). A66456

Numbers k such that (268·10^k - 1)/3 is prime. A293531

Number of equivalence classes of n X n matrices over {0,1} with rows and columns summing to 4, where equivalence is defined by row and column permutations. Also number of isomorphism classes of bicolored quartic bipartite graphs, where isomorphism cannot exchange the colors. A513

Expansion of 1/((1-x)(1-3x)(1-4x)(1-12x)). A21404