Properties of the Number 845

Eight Hundred Forty-Five

Basics

Value: 844 → 845 → 846

Parity: odd

Prime: No

Previous Prime: 839

Next Prime: 853

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 5 × 13 ²

Divisors: 1, 5, 13, 65, 169, 845

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1101001101

Octal: 1515

Duodecimal: 5A5

Hexadecimal: 34d

Square: 714025

Square Root: 29.068883707497267

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

Odd numbers of the form p^1+4k * r², where p is prime of the form 1+4m, r > 1, and gcd(p,r) = 1. (Euler's criteria for odd perfect numbers). A228058

Sequence and first differences (A030124) together list all positive numbers exactly once. A5228

a(n) = 4*(n+1)*n + 5. A78370

Coordination sequence for "ubt" 3D uniform tiling. A299291

Monotonic ordering of set S generated by these rules: if·and y are in S then x² + y² is in S, and 1 is in S. A192476

a(n) = 5·n². A33429

a(n) = n² + 4. A87475

Sum of squares of primes dividing n. A5063

Expansion of 1/(1 - x - x² + x⁵ - x⁷). A204631

Numbers whose sum of digits is 17. A166370