Properties of the Number -1261

Two Hundred Sixty-One

Basics

Value: -1262 → -1261 → -1260

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 10

Digital Root: 1

Palindrome: No

Factorization: 13 × 97

Divisors: 1, 13, 97, 1261

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10011101101

Octal: -2355

Duodecimal: -891

Hexadecimal: -4ed

Square: 1590121

Square Root: 35.510561809129406

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

Expansion of x²/((1-2·x)*(1+3·x)). A91005

Numerators of the characteristic polynomials of the von Mangoldt function matrix. A260237

Numerators of the partial alternating sums of the reciprocals of the alternating sum of divisors function (A206369). A379621

Numerators of second column of the inverse of the triangle of polynomial coefficients P(0,x)=1, 2P(n,x)=(1+x)*[(1+x)^n-1+x^n-1]. A141424

Autosequence preceding A198631(n)/A006519(n+1). Numerators. A233808

a(n,m) =Floor[N[(-2 + Sqrt[3])ⁿ + (-2 - Sqrt[3])ⁿ]/2^m]. A117809

Central polygonal numbers: a(n) = n² - n + 1. A2061

Hex (or centered hexagonal) numbers: 3·n*(n+1)+1 (crystal ball sequence for hexagonal lattice). A3215

a(n) = ∑_{d divides n} q(d), where q(d) = A000009 = number of partitions of d into distinct parts. A47966

Centered 12-gonal numbers, or centered dodecagonal numbers: numbers of the form 6·k*(k-1) + 1. A3154