Properties of the Number 81541

Eighty-One Thousand Five Hundred Forty-One

Basics

Value: 81540 → 81541 → 81542

Parity: odd

Prime: No

Previous Prime: 81533

Next Prime: 81547

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 73 × 1117

Divisors: 1, 73, 1117, 81541

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011111010000101

Octal: 237205

Duodecimal: 3B231

Hexadecimal: 13e85

Square: 6648934681

Square Root: 285.55384781158176

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 4 X 4 symmetric magic squares with line sum 2n. A93198

Number of 5Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4. A241360

First of 5 consecutive semiprimes congruent to 1,2,3,4,5 (mod 6). A367104

T(n,k) = Number of n X k 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4. A241356

Triangle read by rows: the n-th row contains n numbers sorted in decreasing value, each build by dropping a different number from the sequence [n,n-1,n-2,....,1] and concatenating the n-1 others. By definition the first row contains 0. A81541