Properties of the Number 289

Two Hundred Eighty-Nine

Basics

Value: 288 → 289 → 290

Parity: odd

Prime: No

Previous Prime: 283

Next Prime: 293

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 17 ²

Divisors: 1, 17, 289

Polygonal

Triangular: No

Square: Yes

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100100001

Octal: 441

Duodecimal: 201

Hexadecimal: 121

Square: 83521

Square Root: 17

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: Yes

Fermat Number: No

Cullen Number: No

OEIS Sequences

The squares: a(n) = n². A290

Perfect powers: m^k where m > 0 and k >= 2. A1597

Squares of primes. A1248

Powerful numbers, definition (1): if a prime p divides n then p² must also divide n (also called squareful, square full, square-full or 2-powerful numbers). A1694

Quarter-squares: a(n) = floor(n/2)*ceiling(n/2). Equivalently, a(n) = floor(n²/4). A2620

Odd squares: a(n) = (2n+1)². Also centered octagonal numbers. A16754

Lucky numbers. A959

Triangle read by rows: T(n,k), n >= 1, k >= 1, in which column k lists k copies of the positive squares in nondecreasing order, and the first element of column k is in row k(k+1)/2. A236104

1 and the prime powers p^m where m >= 2, thus excluding the primes. A25475

Squares and twice squares. A28982