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Properties of the Number 18805

Eighteen Thousand Eight Hundred Five

Basics

Value: 18804 → 18805 → 18806

Parity: odd

Prime: No

Previous Prime: 18803

Next Prime: 18839

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 5 × 3761

Divisors: 1, 5, 3761, 18805

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100100101110101

Octal: 44565

Duodecimal: AA71

Hexadecimal: 4975

Square: 353628025

Square Root: 137.13132391981054

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

Number of series-reduced planted trees with n leaves of 2 colors. A50381
T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0, 1 or 2 neighboring 1s. A297374
Number of non-strict integer partitions of n with at least one part of odd multiplicity that is not the first or last. A349796
Array read by antidiagonals: T(n,k) is the number of series-reduced rooted trees with n leaves of k colors. A319254
Let A(n) = #{(i,j,k): i2 + j2 + k2 <= n}, V(n) = (4/3)*π*n3/2, P(n) = A(n) - V(n); A000092 gives values of n where |P(n)| sets a new record; sequence gives A(A000092(n)). A413
Positions of pandigital 10-digit numbers after the decimal point in the decimal expansion of π. A280183
Number of compositions of n with exactly 4 adjacent equal parts. A106360
Start from the singleton set S = {n}, and unless 1 is already a member of S, generate on each iteration a new set where each odd number k is replaced by 3k+1, and each even number k is replaced by 3k+1 and k/2. a(n) is the total size of the set from the singleton through after the first iteration which has produced 1 as a member, inclusive. A291213
Number of n X 3 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0, 1 or 2 neighboring 1s. A297369
Number of 5Xn 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0, 1 or 2 neighboring 1s. A297378