ℕ atory
Play Now

Properties of the Number 28785

Twenty-Eight Thousand Seven Hundred Eighty-Five

Basics

Value: 28784 → 28785 → 28786

Parity: odd

Prime: No

Previous Prime: 28771

Next Prime: 28789

Digit Sum: 30

Digital Root: 3

Palindrome: No

Factorization: 3 × 5 × 19 × 101

Divisors: 1, 3, 5, 15, 19, 57, 95, 101, 285, 303

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 111000001110001

Octal: 70161

Duodecimal: 147A9

Hexadecimal: 7071

Square: 828576225

Square Root: 169.66142755499848

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

Triangular array T(n,k), read by rows: coefficients of strong divisibility sequence of polynomials p(1,x) = 1, p(2,x) = 1 + 5x, p(n,x) = u·p(n-1,x) + v·p(n-2,x) for n >=3, where u = p(2,x), v = 1 - x - x2. A367210
T(n,k)=Number of length n+5 0..k arrays with no six consecutive terms having the maximum of any two terms equal to the minimum of the remaining four terms. A249960
Numbers k such that k3 divides 14k2 + 1. A177814
a(n) = number of set partitions of {1, 2, ..., n} whose blocks consist only of elements that differ by two or less (that is, have only the forms {i}, {i,i+1}, {i,i+2}, or {i,i+1,i+2}). A129847
Recurrence derived from the decimal places of sqrt(2). a(0)=0, a(i+1)=position of first occurrence of a(i) in decimal places of sqrt(2). A98326
Number of rooted trees with n nodes with every leaf at height 4. A48809
Number of rooted identity trees with n nodes and 3 leaves. A55328
Number of (w,x,y,z) with all terms in {1,...,n} and w <= x > y <= z. A212246
Numbers k such that k and k2 use only the digits 2, 5, 6, 7 and 8. A137111
a(n) = numerator of constant λ(n) involved in a recurrence for the Atkin polynomials Ak(j). A145226