Properties of the Number 21058

Twenty-One Thousand Fifty-Eight

Basics

Value: 21057 → 21058 → 21059

Parity: even

Prime: No

Previous Prime: 21031

Next Prime: 21059

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 × 10529

Divisors: 1, 2, 10529, 21058

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2730 Try Today's Challenge

Representations

Binary: 101001001000010

Octal: 51102

Duodecimal: 1022A

Hexadecimal: 5242

Square: 443439364

Square Root: 145.11374848717816

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

Numbers k such that the decimal digits of φ(k) are a permutation of those of k. A115921

Greatest number having exactly n representations as ab+ac+bc with 0 < a < b < c. A94377

Greatest number having exactly n representations as ab+ac+bc with 1 <= a <= b <= c. A94380

Sum of the numbers already killed in the first jump of a Sieve of Eratosthenes table. A179628

Coordination sequence for MgNi2, Position Ni1. A9933

Number of partitions satisfying 0 < cn(1,5) + cn(4,5). A39898

Number of nondecreasing arrangements of n numbers in -3..3 with sum zero and sum of squares not greater than n·12/3. A183921

Composite numbers, not ending with 0, sharing a 3-digit sequence with some of its prime factors. A131523

G.f. satisfies: A(x) = 1 + x·A(x)²*A(x·A(x)²). A88717

Decimal expansion of 1/54. A21058