Properties of the Number -1971

Nine Hundred Seventy-One

Basics

Value: -1972 → -1971 → -1970

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ³ × 73

Divisors: 1, 3, 9, 27, 73, 219, 657, 1971

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11110110011

Octal: -3663

Duodecimal: -1183

Hexadecimal: -7b3

Square: 3884841

Square Root: 44.395945760846224

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

Reversion of partitions into distinct parts A000009. A50393

G.f. A(x) satisfies: A(x)^-3 + A(-x)^-3 = 2 and A(x)³ - A(-x)³ = 18·x. A196865

G.f. A(x,y) = ∑_n>=0 xⁿ/(1-y)^2·n+1 * ∑_k=0..3·n T(n,k)*y^k satisfies: y = ∑_n=-oo..+oo (-1)ⁿ * x^n*(n+1/2) * A(x,y)ⁿ. A355870

a(n) = 6ⁿ - n⁷. A24069

Expansion of e.g.f. cos(x)*cos(log(1+x)). A9097

Numerators of hypergeometric Cauchy numbers c_3,n. A224091

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 421", based on the 5-celled von Neumann neighborhood. A272052

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 473", based on the 5-celled von Neumann neighborhood. A272426

arctan(arcsin(tanh(x)))=x-3/3!*x³+49/5!*x⁵-1971/7!*x⁷+147457/9!*x⁹... A12126

Numbers > 1000 such that all the substrings of length = 3 are primes (substrings with leading '0' are considered to be nonprime). A211684