Properties of the Number 27980

Twenty-Seven Thousand Nine Hundred Eighty

Basics

Value: 27979 → 27980 → 27981

Parity: even

Prime: No

Previous Prime: 27967

Next Prime: 27983

Digit Sum: 26

Digital Root: 8

Palindrome: No

Factorization: 2 ² × 5 × 1399

Divisors: 1, 2, 4, 5, 10, 20, 1399, 2798, 5596, 6995

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110110101001100

Octal: 66514

Duodecimal: 14238

Hexadecimal: 6d4c

Square: 782880400

Square Root: 167.27223320085136

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

24 'Reverse and Add' steps are needed to reach a palindrome. A65318

Number of one-element transitions among partitions of the integer n for unlabeled parts. A93695

a(n+1)-+a(n)=prime, a(n+1)*a(n)=Average of twin prime pairs, a(1)=1,a(2)=4. A154493

T(n,k) = Number of n X k 0..3 arrays with exactly floor(n X k/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order. A222275

a(n) = 1000·n - 20. A157515

Number of nX3 0..3 arrays with exactly floor(nX3/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order. A222271

G.f. A(x) satisfies: A( A(x)² ) = C(x) * A(x), where C(x) = x + C(x)², with A(0)=0, A'(0)=1. A272483

a(n) = ∑_k=0..n-1 T(n,k)*T(n,2n-k), T given by A027960. A27980

Number of perfect matchings in graph C₁₀ X P_n. A28481

Numbers n such that prime(n) contains a substring of all the prime digits in order, i.e., "2357". A295708