Properties of the Number 28985

Twenty-Eight Thousand Nine Hundred Eighty-Five

Basics

Value: 28984 → 28985 → 28986

Parity: odd

Prime: No

Previous Prime: 28979

Next Prime: 29009

Digit Sum: 32

Digital Root: 5

Palindrome: No

Factorization: 5 × 11 × 17 × 31

Divisors: 1, 5, 11, 17, 31, 55, 85, 155, 187, 341

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 111000100111001

Octal: 70471

Duodecimal: 14935

Hexadecimal: 7139

Square: 840130225

Square Root: 170.2498164463034

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

Numbers that are sums of 2 or more consecutive squares in more than 1 way. A62681

Expansion of sec(arctanh(x)). A102075

Numbers m such that Stern polynomial B(m,x) has no irreducible polynomial factors that themselves are Stern polynomials. The initial a(1) = 1 is included by convention. A389918

a(n) is the number m such that f(sqrt(n)) is in the field Q(sqrt(m)), where f(x) is defined from the continued fraction x = [c(0),c(1),...] as [c(0)+2, c(1)+2,...]. A229958

Squarefree numbers which yield zero when their prime factors are xored together. A235488

Triangle read by rows: T(n,k) appears in the transformation ∑_k=0..n (k+1)*x^k = ∑_k=0..n T(n,k)*(x+k)^k. A247236

Place two n-gons with radii 1 and 2 concentrically, forming an annular area between them. Connect all the vertices with line segments that lie entirely within that area. Then a(n) is the number of regions in that figure. A337700

a(n) is the number m such that f(sqrt(n)) is in the field Q(sqrt(m)), where f(x) is defined from the continued fraction x = [c(0), c(1), ... ] as [1/c(0), 1/c(1), ...]. A229956

a(n) = (1/24)*n*(n - 1)*(n - 3)*(n - 14). A319930

Irregular triangle read by rows: T(n, k) is the q-multinomial coefficient defined by the k-th partition of n in Abramowitz-Stegun order, evaluated at q = 4. A347487