Properties of the Number -1825

Eight Hundred Twenty-Five

Basics

Value: -1826 → -1825 → -1824

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 5 ² × 73

Divisors: 1, 5, 25, 73, 365, 1825

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11100100001

Octal: -3441

Duodecimal: -1081

Hexadecimal: -721

Square: 3330625

Square Root: 42.720018726587654

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

Expansion of 1/∑_k>=0 x^k². A317665

Triangle T(n,k), read by rows, defined by T(n,k)=3·T(n-1,k)-T(n-1,k-1)-T(n-2,k), T(0,0)=1, T(1,0)=2, T(1,1)=-1, T(n,k)=0 if k<0 or if k>n. A123971

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 147", based on the 5-celled von Neumann neighborhood. A270293

Square array read by antidiagonals downwards: A(n, k) = (∑_i=1..n i^k) - (n+1)^k for n >= 1, k >= 1. A290844

Coefficients of period polynomials. A6309

Numbers k such that (8·10^k + 49)/3 is prime. A270890

Octagonal numbers: n*(3·n-2). Also called star numbers. A567

Generalized octagonal numbers: k*(3·k-2), k=0, +- 1, +- 2, +-3, ... A1082

Odd numbers of the form p^1+4k * r², where p is prime of the form 1+4m, r > 1, and gcd(p,r) = 1. (Euler's criteria for odd perfect numbers). A228058

Triangular numbers plus quarter squares: n*(n+1)/2 + floor(n²/4) (i.e., A000217(n) + A002620(n)). A6578