Properties of the Number 21422

Twenty-One Thousand Four Hundred Twenty-Two

Basics

Value: 21421 → 21422 → 21423

Parity: even

Prime: No

Previous Prime: 21419

Next Prime: 21433

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 2 × 10711

Divisors: 1, 2, 10711, 21422

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001110101110

Octal: 51656

Duodecimal: 10492

Hexadecimal: 53ae

Square: 458902084

Square Root: 146.36256351950112

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 T(n,k) of equivalence classes of ways of placing k 2 X 2 tiles in an n X 10 rectangle under all symmetry operations of the rectangle; irregular triangle T(n,k), n>=2, 0<=k<=5·floor(n/2), read by rows. A238586

3-comma numbers: n occurs in the sequence S[k+1]=S[k]+10·last_digit(S[k-1])+first_digit(S[k]) for three different splittings n=concat(S[0],S[1]). A166513

Successive differences of A000990. A147766

Numerators of continued fraction convergents to sqrt(978). A42892

Number of 5 X 5 X 5 triangular nonnegative integer arrays, symmetric under 120 degree rotation, with all sums of an element and its neighbors <= n. A166213

Number of (w,x,y,z) with all terms in {0,...,n} and |w-x|+|x-y+|y-z|=n. A212904

G.f. A(x) satisfies: 0 = ∑_n=-oo..+oo (-1)ⁿ * x^2·n * (A(x) - xⁿ)ⁿ * (1 - xⁿ*A(x))ⁿ. A363138

Coefficients of a polynomial used in calculation of A055913. A55916

Sum of the numbers of unitary divisors of the binomial coefficients C(n,k), k=0..n. A103445

Numbers k such that 3^k + 2^k + 10 is prime. A219617