Properties of the Number 9990

Nine Thousand Nine Hundred Ninety

Basics

Value: 9989 → 9990 → 9991

Parity: even

Prime: No

Previous Prime: 9973

Next Prime: 10007

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 2 × 3 ³ × 5 × 37

Divisors: 1, 2, 3, 5, 6, 9, 10, 15, 18, 27

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 10011100000110

Octal: 23406

Duodecimal: 5946

Hexadecimal: 2706

Square: 99800100

Square Root: 99.9499874937461

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 in which 9 outnumbers all other digits together. A292739

The sum of the first n terms of the sequence is the concatenation of the first n digits of the sequence, with a(1) = 1. A300000

Bessel polynomial {y_n}'(1). A1514

List the positions of all digits 9 in the concatenation of all terms, not necessarily in order. This is the lexicographically earliest such sequence. A210423

a(n) = n⁴ - n. A58895

Numbers m such that the largest digit in the decimal expansion of 1/m is 1. A333402

Numbers n that raised to the powers from 1 to k (with k>=1) are multiple of the sum of their digits (n raised to k+1 must not be a multiple). Case k=9. A135194

a(n) = n*(5·n-3). A135706

Generalized Mancala solitaire (A002491); to get n-th term, start with n and successively round up to next 11 multiples of n-1, n-2, ..., 1, for n>=1. A113748

Numbers whose set of base 10 digits is {0,9}. A97256