Properties of the Number 24021

Twenty-Four Thousand Twenty-One

Basics

Value: 24020 → 24021 → 24022

Parity: odd

Prime: No

Previous Prime: 24019

Next Prime: 24023

Digit Sum: 9

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 17 × 157

Divisors: 1, 3, 9, 17, 51, 153, 157, 471, 1413, 2669

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101110111010101

Octal: 56725

Duodecimal: 11A99

Hexadecimal: 5dd5

Square: 577008441

Square Root: 154.98709623707387

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

T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order. A222378

Numbers k that are equal to the product of the largest triangular proper divisor of k and the sum of all triangular proper divisors of k. A225881

a(n) = 100·n² + 100·n + 21. A152161

Number of nX2 0..3 arrays with no more than floor(nX2/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order. A222373

G.f. satisfies: A(x) = ∑_n>=0 xⁿ * ∑_k=0..n C(n,k) * (A(x)^k - x^k)^k * x^k*(n-k). A245107

Numbers whose sum of triangular divisors is also a divisor and greater than 1. A209311

a(n) = prime(n)² - 4·prime(n). A245034

Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 187", based on the 5-celled von Neumann neighborhood. A270675

Largest cost for a permutation problem. A367185

T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..3 order. A222679