Properties of the Number -1217

Two Hundred Seventeen

Basics

Value: -1218 → -1217 → -1216

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 1217

Divisors: 1, 1217

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10011000001

Octal: -2301

Duodecimal: -855

Hexadecimal: -4c1

Square: 1481089

Square Root: 34.88552708502482

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) = -n² + 9·n + 23. A126719

Regular triangle, T(n, k) = f(n, k) - f(n, 0) + 1, where f(n, k) = ∑_j=0..k (-1)^j*StirlingS2(n, n-j)*binomial(n,j) + ∑_j=0..n-k (-1)^j*StirlingS2(n, n-j)*binomial(n, j), read by rows. A176156

Expansion of tanh(x)*cos(sin(x)). A9825

Prime-indexed primes: primes with prime subscripts. A6450

Primes of the form 2x² + 2xy + 17y². A139827

Primes of form 8n+1, that is, primes congruent to 1 mod 8. A7519

Primes of form 10n+7. A30432

Larger member p+4 of cousin primes (p, p+4). A46132

Primes whose decimal representation is a valid number in base 9 and interpreted as such is again a prime. A235395

Describe n. Also called the "Say What You See" or "Look and Say" sequence LS(n). A45918