Properties of the Number 55991

Fifty-Five Thousand Nine Hundred Ninety-One

Basics

Value: 55990 → 55991 → 55992

Parity: odd

Prime: No

Previous Prime: 55987

Next Prime: 55997

Digit Sum: 29

Digital Root: 2

Palindrome: No

Factorization: 13 × 59 × 73

Divisors: 1, 13, 59, 73, 767, 949, 4307, 55991

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1101101010110111

Octal: 155267

Duodecimal: 2849B

Hexadecimal: dab7

Square: 3134992081

Square Root: 236.62417458915732

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

Numerator of 1/n + 2/(n-1) + 3/(n-2) + ... + (n-1)/2 + n. A27612

Numerator - denominator in n-th harmonic number, 1 + 1/2 + 1/3 + ... + 1/n. A64169

a(n) = (H(n) - 1)*lcm{1,...,n}, where H(n) is the n-th harmonic number. A27457

Triangle of numerators in the square of the matrix A[i,j] = 1/i for j <= i, 0 otherwise. A119947

a(n) = running sum of the first n harmonic numbers, multiplied by the LCM of 1..n. A81530

a(n) is the length of stage n in A137843. A291753

Numerator of the Harary number for the path graph P_n. A160048

Numbers such that the sequence of all possible sums of divisors of n is increasing but not strictly so, the sums being ordered by their characteristic functions, seen as binary numbers (see example). A230492

Erroneous version of A027612. A81525

Numerators of row sums of array of rationals A038566(n)/A020653(n), n>=2. A111992