Properties of the Number 20025

Twenty Thousand Twenty-Five

Basics

Value: 20024 → 20025 → 20026

Parity: odd

Prime: No

Previous Prime: 20023

Next Prime: 20029

Digit Sum: 9

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 5 ² × 89

Divisors: 1, 3, 5, 9, 15, 25, 45, 75, 89, 225

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 100111000111001

Octal: 47071

Duodecimal: B709

Hexadecimal: 4e39

Square: 401000625

Square Root: 141.50971698084905

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 (n+2)X(k+2) 0..4 arrays with every 3X3 subblock row and column sum prime and every diagonal and antidiagonal sum nonprime. A251885

Numbers k such that 29^k + 2 is prime. A87886

G.f.: ∑_n>=0 n! * x^n*(n+1/2) / ∏_k=1..n (1 - k·x^k). A204858

Terms k of A228058 for which A048146(k)+A162296(k) >= 2·k, where A048146 is the sum of non-unitary divisors, and A162296 is the sum of divisors that have a square factor. A389219

Numbers that match polynomials over {0,1} that have a factor containing -3 as a coefficient; see Comments. A208182

Triangle read by rows: T(n,k) is the number of achiral colorings of the edges of a regular n-D orthotope (or ridges of a regular n-D orthoplex) using exactly k colors. Row n has n·2^n-1 columns. A338145

Triangle read by rows: T(n,k) is the number of achiral colorings of the edges of a regular n-D orthoplex (or ridges of a regular n-D orthotope) using exactly k colors. Row 1 has 1 column; row n>1 has 2·n*(n-1) columns. A338149

Numbers k in A228058 such that also A001065(k) is in A228058. A325380

a(n) = (5·2ⁿ⁺² - 3·n*2ⁿ - 2*(-1)ⁿ) / 18. A139790

Index of first occurrence of n in A348179, or -1 if n never appears. A349423