Properties of the Number 20895

Twenty Thousand Eight Hundred Ninety-Five

Basics

Value: 20894 → 20895 → 20896

Parity: odd

Prime: No

Previous Prime: 20887

Next Prime: 20897

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 5 × 7 × 199

Divisors: 1, 3, 5, 7, 15, 21, 35, 105, 199, 597

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 101000110011111

Octal: 50637

Duodecimal: 10113

Hexadecimal: 519f

Square: 436601025

Square Root: 144.55102905202716

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

Centered tetrahedral numbers. A5894

In the '3x+1' problem, these values for the starting value set new records for highest point of trajectory before reaching 1. A6884

Integers of the form 8k + 7 that can be written as a sum of four distinct squares of the form m, m + 1, m + 3, m + 5, where m == 2 (mod 4). A243580

Pseudo-random numbers: Davenport's generator for 32-bit integers. A84277

Number of labeled rooted polygonal cacti (Husimi graphs) with n nodes. A35087

Least number whose Collatz 3x+1 trajectory contains a number >= 2ⁿ. A222292

First differences of A260443. A277197

Triangle T(n,k) read by rows: coefficient [x^k] of the polynomial ∑_{k=0..infinity} (2·k+1)ⁿ*binomial(x,k) / 2^x. A176668

a(n) is the smallest positive integer which can be represented as the sum of distinct nonzero icosahedral numbers in exactly n ways, or -1 if no such integer exists. A360215

Expansion of ∏_k>=1 (1 + x^k) * (1 + x^k²) * (1 + x^k³). A369575