Properties of the Number 81205

Eighty-One Thousand Two Hundred Five

Basics

Value: 81204 → 81205 → 81206

Parity: odd

Prime: No

Previous Prime: 81203

Next Prime: 81223

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 5 × 109 × 149

Divisors: 1, 5, 109, 149, 545, 745, 16241, 81205

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 10011110100110101

Octal: 236465

Duodecimal: 3ABB1

Hexadecimal: 13d35

Square: 6594252025

Square Root: 284.96491012052695

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

Sum T(n,k) of the k-th last entries in all blocks of all set partitions of [n]; triangle T(n,k), n>=1, 1<=k<=n, read by rows. A286897

Number of n X 3 arrays of the minimum value of corresponding elements and their horizontal, vertical or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..1 n X 3 array. A219699

Centered square numbers which are sphenic numbers. A380882

Staircase on Pascal's triangle. A81205