Properties of the Number 51221

Fifty-One Thousand Two Hundred Twenty-One

Basics

Value: 51220 → 51221 → 51222

Parity: odd

Prime: No

Previous Prime: 51217

Next Prime: 51229

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 17 × 23 × 131

Divisors: 1, 17, 23, 131, 391, 2227, 3013, 51221

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 1100100000010101

Octal: 144025

Duodecimal: 25785

Hexadecimal: c815

Square: 2623590841

Square Root: 226.32056910497553

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

Terms of A324315 (squarefree integers m > 1 such that if prime p divides m, then the sum of the base p digits of m is at least p) that are also octagonal numbers (A000567) with index equal to their largest prime factor. A324320

Number of ways to place 4 nonattacking kings on a 4 X n board. A172203

Number of solid partitions of n supported on graph of cube. A3404

Octagonal numbers which are the sums of exactly two positive octagonal numbers. A136346

Octagonal numbers with prime indices. A267144

3-almost prime octagonal numbers. A129927

a(n) = n! * ∑_{k=0..floor(n/3)} (k+1)^k-1 / (6^k * k! * (n-3·k)!). A362525

Octagonal numbers that are the product of three distinct primes. A382231

Numbers of the form 10^x-y² >= 0. A51221