Properties of the Number -2645

Six Hundred Forty-Five

Basics

Value: -2646 → -2645 → -2644

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 5 × 23 ²

Divisors: 1, 5, 23, 115, 529, 2645

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -101001010101

Octal: -5125

Duodecimal: -1645

Hexadecimal: -a55

Square: 6996025

Square Root: 51.42956348249516

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

Number of partitions of n such that no part is a sum of two other parts. A236912

a(n) = 5·n². A33429

Number of partitions of n into parts 1/2, 3/4, 7/8, 15/16, etc. A2843

Concentric pentagonal numbers: floor( 5·n² / 4 ). A32527

a(n) = A005940(1+(1+(3·A156552(n)))) = (1/2) * A005940(1+(3·A156552(2·n))). A329603

Number of integer partitions of n such that more than one set can be obtained by choosing a different divisor of each part. A370803

a(n) = 6·n² - 1. A140811

X-toothpick sequence on Z³ lattice (see Comments for precise definition). A160170

The Collatz or 3x+1 map (A006370) conjugated by unary-binary-encoding (A156552). A341515

Numbers with ordered prime signature (1,2). A95990