Properties of the Number -161

One Hundred Sixty-One

Basics

Value: -162 → -161 → -160

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 8

Digital Root: 8

Palindrome: Yes

Factorization: 7 × 23

Divisors: 1, 7, 23, 161

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10100001

Octal: -241

Duodecimal: -115

Hexadecimal: -a1

Square: 25921

Square Root: 12.68857754044952

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

Irregular triangle read by rows: row n is the expansion of (1 + 2·x - x²)ⁿ. A123199

Triangle read by rows: the n-th row consists of the coefficients in the expansion of ∑_j=0..n A123162(n,j)*x^j*(1 - x)^{n - j}. A123217

a(n) = nearest integer to n² * cos(sqrt(n)). A274090

Take alternate terms of A274088 and A274090. A274091

a(n) = nearest integer to k²*sin(sqrt(k)+j*π/2) where n = 3·k+j, 0<=j<3. A274092

T(j,k) are the numerators s in the representation R = s/t + (2/π)*u/v of the resistance between two nodes separated by the distance vector (j,k) in an infinite square lattice of one-ohm resistors, where T(j,k), j >= 0, 0 <= k <= j, is a triangle read by rows. A355565

Expansion of (1-x-x^N)/((1-x)(1-x²)(1-x³)...(1-x^N)) for N = 3. A60022

Poly-Cauchy numbers of the second kind hat c_n^-3. A223901

Expansion of φ(-x) * χ(-x) in powers of·where φ(), χ() are Ramanujan θ functions. A132970

Numerator of Hermite(n, 1/18). A159545