Properties of the Number -621

Six Hundred Twenty-One

Basics

Value: -622 → -621 → -620

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 9

Digital Root: 9

Palindrome: No

Factorization: 3 ³ × 23

Divisors: 1, 3, 9, 23, 27, 69, 207, 621

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -1001101101

Octal: -1155

Duodecimal: -439

Hexadecimal: -26d

Square: 385641

Square Root: 24.919871588754223

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/(1 + x - x³ - x⁴ - x⁸ - x¹² - x¹³ - x¹⁷ - x²¹ - x²² - x²⁶ - x³⁰ - x³¹ + x³³ + x³⁴). A173908

E.g.f. A(x) satisfies: (A(x)⁵ - 10·x)² = (2 - A(x)²)⁵. A249787

Partial alternating sums of Pillai's arithmetical function (A018804). A370895

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

G.f. L(x,y) satisfies: L(x,y) = x * (1 + y·x*L'(x,y)) / (1 + x·L'(x,y)) where L'(x,y) = d/dx L(x,y), as a triangle read by rows. A301305

Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of 2/(1 + k·x + sqrt(1 + 2·k*x + k*(k+4)*x²)). A307968

G.f. A(x) satisfies A(x) = ( 1 + 9·x*(1 + x)*A(x) )^1/3. A372038

Numerator of Hermite(n, 9/10). A159279

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 342", based on the 5-celled von Neumann neighborhood. A269512

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 211", based on the 5-celled von Neumann neighborhood. A270900