Properties of the Number 17980

Seventeen Thousand Nine Hundred Eighty

Basics

Value: 17979 → 17980 → 17981

Parity: even

Prime: No

Previous Prime: 17977

Next Prime: 17981

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 2 ² × 5 × 29 × 31

Divisors: 1, 2, 4, 5, 10, 20, 29, 31, 58, 62

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100011000111100

Octal: 43074

Duodecimal: A4A4

Hexadecimal: 463c

Square: 323280400

Square Root: 134.08952233489387

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

Numbers n such that σ(n) = 6*φ(n). A104900

25-gonal numbers: a(n) = n*(23·n-21)/2. A255184

Array read by columns: T(n,m) = number of unlabeled graphs with n vertices and m unicyclic components. A137918

a(n) = binomial(2·n,n) mod ((n+1)*(n+2)*(n+3)). A65345

Number of L-shaped tiles in all tilings of a 2 X n board with 1 X 1 and L-shaped tiles (where the L-shaped tiles cover 3 squares). A127866

Positions of zeros in A165597. A165598

a(n) = ∑_i=0..n digsum₇(i)⁴, where digsum₇(i) = A053828(i). A231679

Row sums of triangular matrix A246381 = exp(L) where L(n,k) = C(2·n, 2·k+1)/2. A246385

a(n) = 2·n*(n+1)*(n+2)/3. A210440

Square table where T(n,k) = binomial(n*(n+k), k) * n/(n+k), for n>=1, k>=0, as read by antidiagonals. A299427