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Properties of the Number 21345

Twenty-One Thousand Three Hundred Forty-Five

Basics

Value: 21344 → 21345 → 21346

Parity: odd

Prime: No

Previous Prime: 21341

Next Prime: 21347

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 5 × 1423

Divisors: 1, 3, 5, 15, 1423, 4269, 7115, 21345

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001101100001

Octal: 51541

Duodecimal: 10429

Hexadecimal: 5361

Square: 455609025

Square Root: 146.0992813124007

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 (12345, 13245, 21345, 23145, 31245, 32145)-avoiding permutations. A54872
Permutations of 12345: Numbers having each of the decimal digits 1,...,5 exactly once, and no other digit. A178475
Number of distinct values of ∑i=0..n x(i)*binomial(n,i), where the x(i) is a vector of length n+1 that runs through all combinations of {0, 1}. A205536
Where record values of A119999 occur. A120001
Numbers with 5 distinct digits {1,2,3,4,5} such that all adjacent digits (as well as first and last digits) are coprime. A104972
List of André permutations of the first kind. A278982
Array read by rows in which the n-th row contains the multiples of n in increasing order using all the digits of first n numbers. A78189
a(n) = ∑i=1..n ((i+1)i - 1)/i. A175151
Decimal representation of permutations of lengths 1, 2, 3, ... arranged first by number of inversions and then lexicographically. A268532
Number of up-down permutations p of [n] such that for all i<n-1 the number of elements p(j) between p(i) and p(i+1) for j>i+1 differs from the number of elements p(k) between p(i+1) and p(i+2) for k>i+2. A367495