Properties of the Number -218791

Two Hundred Eighteen Thousand Seven Hundred Ninety-One

Basics

Value: -218792 → -218791 → -218790

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 28

Digital Root: 1

Palindrome: No

Factorization: 331 × 661

Divisors: 1, 331, 661, 218791

Polygonal

Triangular: Yes

Square: No

Pentagonal: No

Hexagonal: Yes

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -110101011010100111

Octal: -653247

Duodecimal: -A6747

Hexadecimal: -356a7

Square: 47869501681

Square Root: 467.75100213682066

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

Strong pseudoprimes to base 3. A20229

Numbers of the form p·q, p and q prime with q=2·p-1. A129521

Triangular numbers which are the product of two primes. A68443

Odd numbers with increasing numbers of bases to which they are strong pseudoprimes. A141768

Composite numbers k == 5, 7 (mod 12) such that 3^(k-1/2) == -1 (mod k). A375918

Triangular numbers which are sums of three consecutive primes. A167788

Odd numbers > 1, not powers of primes, for which A326147(n) is equal to abs(A326146(n)). A326148

Numbers m such that exactly half of the a such that 0<a<m and (a,m)=1 satisfy a^m-1 == 1 (mod m). A191311

Odd non-Carmichael numbers with increasing numbers of bases to which they are pseudoprimes. A194946

Record values in A265388. A265395