Properties of the Number 28905

Twenty-Eight Thousand Nine Hundred Five

Basics

Value: 28904 → 28905 → 28906

Parity: odd

Prime: No

Previous Prime: 28901

Next Prime: 28909

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 5 × 41 × 47

Divisors: 1, 3, 5, 15, 41, 47, 123, 141, 205, 235

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 111000011101001

Octal: 70351

Duodecimal: 14889

Hexadecimal: 70e9

Square: 835499025

Square Root: 170.01470524634038

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

Let P1>=3, P2, P3 be consecutive primes, with P3-P2=2. a(n)=(P2+P3)/12 when P2-P1 sets a record. A329158

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

Let P1 >= 3, P2, P3 be consecutive primes, with P3 - P2 = 2. a(n) = (P2 + P3)/12 for the first occurrence of (P2 - P1)/2 = n. A329251

a(n) = 25·n² + 5. A158445

a(n) = (prime(n))² - (nonprime(n))². A161757

[ n(n-1)(n-2)(n-3)/17 ]. A11927

Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 68. A31746

a(3n) = a(3n-1)+a(3n-2), a(3n+1) = a(3n)*a(3n-1), a(3n+2) = a(3n+1)/a(3n). A174529

Number of length 5 1..(n+1) arrays with every leading partial sum divisible by 2, 3 or 5. A254832

6·a(n) - 1 is the least prime p of a pair of twin primes p, p + 2, for which the prime gap immediately below p achieves the size 2·A007494(n). A337435