Properties of the Number 21700

Twenty-One Thousand Seven Hundred

Basics

Value: 21699 → 21700 → 21701

Parity: even

Prime: No

Previous Prime: 21683

Next Prime: 21701

Digit Sum: 10

Digital Root: 1

Palindrome: No

Factorization: 2 ² × 5 ² × 7 × 31

Divisors: 1, 2, 4, 5, 7, 10, 14, 20, 25, 28

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010011000100

Octal: 52304

Duodecimal: 10684

Hexadecimal: 54c4

Square: 470890000

Square Root: 147.30919862656236

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

a(n) = ∑_k=0..5 binomial(n,k). A6261

Numbers k such that 2^k+1 - 1 is prime. A90748

a(n) = ∑_k=0..n binomial(4·n,k). A66381

Expansion of e.g.f. A(x,y) satisfying A(x,y) = ∑_n>=0 (A(x,y)ⁿ + y)ⁿ * xⁿ/n!, as a triangle read by rows. A361540

Numbers k such that the sum of the squares of the divisors of k is divisible by k. A46762

Numbers n such that n*σ(n) is a perfect square. A69070

Number of partitions of n with rank 3 (the rank of a partition is the largest part minus the number of parts). A101200

Expansion of e.g.f. x·exp(x)*exp(x·exp(x)). A185298

a(n) = n³ + (n+1)³ + (n+2)³ + (n+3)³. A27603

Numbers k such that the harmonic mean of the divisors of k is the square of a rational number. A74266