Properties of the Number -161820

One Hundred Sixty-One Thousand Eight Hundred Twenty

Basics

Value: -161821 → -161820 → -161819

Parity: even

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 2 ² × 3 ² × 5 × 29 × 31

Divisors: 1, 2, 3, 4, 5, 6, 9, 10, 12, 15

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -100111100000011100

Octal: -474034

Duodecimal: -79790

Hexadecimal: -2781c

Square: 26185712400

Square Root: 402.2685670046816

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

4-dimensional figurate numbers: a(n) = (5·n-1)*binomial(n+2,3)/4. A2418

Array T(n,m) = 2*(2m+3)!*(4n+2m+1)!/(m!*(m+2)!*n!*(3n+2m+3)!) read by antidiagonals. A146305

a(n) = (10 / ((3·n+1)*(3·n+2))) * binomial(4·n, n). A197271

Numbers n such that σ(n) = 13*φ(n) (where σ=A000203, φ=A000010). A171258

a(n) = ((2^b-1)/φ(n))*∑_d∣n Moebius(n/d)*d^b-1 for b = 5. A160894