Properties of the Number 25728

Twenty-Five Thousand Seven Hundred Twenty-Eight

Basics

Value: 25727 → 25728 → 25729

Parity: even

Prime: No

Previous Prime: 25717

Next Prime: 25733

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 2 ⁷ × 3 × 67

Divisors: 1, 2, 3, 4, 6, 8, 12, 16, 24, 32

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 110010010000000

Octal: 62200

Duodecimal: 12A80

Hexadecimal: 6480

Square: 661929984

Square Root: 160.39950124610738

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

Smaller member of an infinitary amicable pair. A126169

T(n,k) is the number of (n+1) X (k+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings). A234333

Numbers with prime signature {7,1,1}, i.e., of form p⁷*q·r with p, q and r distinct primes. A179696

E.g.f. C(x,y) = 1 + Integral S(x,y)*C(y,x) dx such that C(x,y)² - S(x,y)² = 1 and C(y,x) = Integral S(y,x)*C(x,y) dy, where C(x,y) = ∑_n>=0 ∑_k=0..n T(n,k) * x^2·n-2·k*y^2·k/((2·n-2·k)!*(2·k)!), as a triangle of coefficients T(n,k) read by rows. A322221

Number of permutations of (1,...,n) having n-6 inversions (n>=6). A5284

E.g.f. C(y,x) = 1 + Integral S(y,x)*C(x,y) dy such that C(y,x)² - S(y,x)² = 1 and C(x,y) = Integral S(x,y)*C(y,x) dx, where C(y,x) = ∑_n>=0 ∑_k=0..n T(n,k) * x^2·n-2·k*y^2·k/((2·n-2·k)!*(2·k)!), as a triangle of coefficients T(n,k) read by rows. A322222

a(n) = ∑_{k=0..floor(n/3)} 2^k * binomial(k,n-3·k)². A387477

Infinitary amicable numbers. A127664

Totients t such that the number of divisors of t equals the number of solutions of φ(x) = t. A305058

E.g.f. C(x,y) = 1 - Integral S(x,y)*C(y,x) dx such that C(x,y)² + S(x,y)² = 1 and S(y,x) = Integral C(y,x)*C(x,y) dy, as a triangle of coefficients T(n,k) read by rows. A367381