Properties of the Number -169

One Hundred Sixty-Nine

Basics

Value: -170 → -169 → -168

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 13 ²

Divisors: 1, 13, 169

Polygonal

Triangular: No

Square: Yes

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10101001

Octal: -251

Duodecimal: -121

Hexadecimal: -a9

Square: 28561

Square Root: 13

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

Rectangular array: A(n,k) = ∑_j=0..k (-1)^floor(j/2)*binomial(k-floor((j+1)/2), floor(j/2))*(-n)^k-j, n >= 1, k >= 0, read by antidiagonals. A299045

a(n) = (5 + (-2)ⁿ)/3. A140966

Coefficients of the '6th-order' mock θ function φ(q). A53268

Alternating partial sums of A000217. A83392

4th differences of partition numbers A000041. A81094

a(n) = 1 + 3·n - 2·n². A168244

G.f.: Re((i·x; x)_inf), where (a; q)_inf is the q-Pochhammer symbol, i = sqrt(-1). A292042

Dirichlet g.f.: 1 / ζ(s-2). A334657

Triangle, read by rows of n*(n+1)/2 terms, where row n equals the coefficients in the series reversion of the function G(x,n)-1 such that: x = ∑_m>=1 1/G(x,n)^n·m * ∏_k=1..m (1 - 1/G(x,n)^k), for n>=1. A214670

Reflected (see A074058) pentanacci numbers A074048. A74062