Properties of the Number 51005

Fifty-One Thousand Five

Basics

Value: 51004 → 51005 → 51006

Parity: odd

Prime: No

Previous Prime: 51001

Next Prime: 51031

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 5 × 101 ²

Divisors: 1, 5, 101, 505, 10201, 51005

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1100011100111101

Octal: 143475

Duodecimal: 25625

Hexadecimal: c73d

Square: 2601510025

Square Root: 225.84286572747877

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 k such that σ(k) = ψ(k) + τ(k). A387953

a(n) = 3·a(n-1) + 2·a(n-2), with a(0)=2, a(1)=7. A7484

T(n,k)=Half the number of nXk binary arrays with no 1 having an adjacent 1 both above and to its left. A184761

T(n,k)=Number of nXk 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or left-upward diagonal neighbors. A208269

Number of subsequences of [ 1,...,n ] in which each even number has an odd neighbor. A7481

Composite numbers k such that σ(k) / d(k) is prime. A48969

Sum of n-th row of A081930. A81932

(10ⁿ)-th primitive antiharmonic number. A228036

Numbers of the form p²*q, with odd primes p > q, such that q divides p-1. A350638

The sum of the totatives of n is a perfect cube. A237282