Properties of the Number 66641

Sixty-Six Thousand Six Hundred Forty-One

Basics

Value: 66640 → 66641 → 66642

Parity: odd

Prime: No

Previous Prime: 66629

Next Prime: 66643

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 103 × 647

Divisors: 1, 103, 647, 66641

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10000010001010001

Octal: 202121

Duodecimal: 32695

Hexadecimal: 10451

Square: 4441022881

Square Root: 258.14918167602235

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 unimodal functions [1..n]->[0..2]. A223718

a(n) is the number of binary (0,1) sequences of length n that have at most two zeros in a window of seven consecutive symbols. A334251

Number of integers in the smallest interval containing both minimal and maximal possible apex values of an addition triangle whose base is a permutation of n+1 consecutive integers. A206604

Numbers k such that Euler φ(k) / Carmichael λ(k) = 34. A66698

Number of walks within N³ (the first octant of Z³) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (0, 0, 1), (0, 1, 0), (0, 1, 1), (1, 1, -1)}. A151094

Partial sums of repdigit numbers (A010785). A277209

E.g.f. A(x) satisfies A(x) = exp( x·cos(x·A(x)^1/2) ). A381308

a(n) = floor(n^sqrt(n)). A66641

a(n) = |{0 < k < n: m = φ(k)/2 + φ(n-k)/12 is an integer with 2^m + prime(m) prime}|, where φ(.) is Euler's totient function. A236344