Properties of the Number -1625

Six Hundred Twenty-Five

Basics

Value: -1626 → -1625 → -1624

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 5 ³ × 13

Divisors: 1, 5, 13, 25, 65, 125, 325, 1625

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11001011001

Octal: -3131

Duodecimal: -B35

Hexadecimal: -659

Square: 2640625

Square Root: 40.311288741492746

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

a(n) = ∑_{k >= 0}(-1)^k*binomial(n,5·k+1). A289321

a(n) = ∑_k>=0 (-1)^k*binomial(n, 5·k+2). A289387

G.f.: exp( ∑_n>=1 A002129(n²)*xⁿ/n ), where A002129(n) is the excess of sum of odd divisors of n over sum of even divisors of n. A225925

Numerator of Hermite(n, 13/14). A159512

a(n) = 5·a(n-1) - 10·a(n-2), with a(0)=0, a(1)=1. A190971

Values of n such that L(13) and N(13) are both prime, where L(k) = (n²+n+1)*2^2·k + (2·n+1)*2^k + 1, N(k) = (n²+n+1)*2^k + n. A227516

Expansion of ((1+x)³ - x³)/((1+x)⁵ - x⁵). A105369

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 219", based on the 5-celled von Neumann neighborhood. A270933

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 459", based on the 5-celled von Neumann neighborhood. A272290

Centered square numbers: a(n) = 2·n*(n+1)+1. Sums of two consecutive squares. Also, consider all Pythagorean triples (X, Y, Z=Y+1) ordered by increasing Z; then sequence gives Z values. A1844