Properties of the Number 20124

Twenty Thousand One Hundred Twenty-Four

Basics

Value: 20123 → 20124 → 20125

Parity: even

Prime: No

Previous Prime: 20123

Next Prime: 20129

Digit Sum: 9

Digital Root: 9

Palindrome: No

Factorization: 2 ² × 3 ² × 13 × 43

Divisors: 1, 2, 3, 4, 6, 9, 12, 13, 18, 26

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

4823 Try Today's Challenge

Representations

Binary: 100111010011100

Octal: 47234

Duodecimal: B790

Hexadecimal: 4e9c

Square: 404975376

Square Root: 141.85908501044267

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(φ(k)) = φ(σ(k)). A33632

T(n,k)=Number of nXk binary arrays without the pattern 0 1 0 diagonally, vertically or horizontally. A188508

Numbers k such that σ(φ(k)) == φ(σ(k)) (mod k), that is, A033632(k)/k is an integer. A92584

Trajectory of n under the Reverse and Add! operation carried out in base 3 (presumably) does not reach a palindrome and (presumably) does not join the trajectory of any term m < n. A77405

Number of permutations of [n] with four inversions. A5287

Numbers k such that σ(φ(k)) divides φ(σ(k)). A73858

Triangle read by rows: T(n,k) is the number of Schroeder paths of length 2n and having k valleys. A101282

Number of partitions of n into distinct parts with boundary size 10. A227567

Smallest k for which a chain of linked rods of length 1, ..., k can be folded in half in exactly n dictinct ways. A390056

Number of lines through exactly 4 points of an n X n grid of points. A18811