Properties of the Number 9978

Nine Thousand Nine Hundred Seventy-Eight

Basics

Value: 9977 → 9978 → 9979

Parity: even

Prime: No

Previous Prime: 9973

Next Prime: 10007

Digit Sum: 33

Digital Root: 6

Palindrome: No

Factorization: 2 × 3 × 1663

Divisors: 1, 2, 3, 6, 1663, 3326, 4989, 9978

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10011011111010

Octal: 23372

Duodecimal: 5936

Hexadecimal: 26fa

Square: 99560484

Square Root: 99.88993943335835

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

T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction. A250783

Number of times the digit 8 appears in the first 10ⁿ digits of π. A99299

Numbers with rounded up arithmetic mean of digits = 9. A178369

T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with no 3x3 subblock diagonal sum 1 and no antidiagonal sum 1 and no row sum 0 or 1 and no column sum 0 or 1. A255159

Number of winning (or reformed) decks at Mousetrap. A7709

O.g.f.: exp( ∑_n>=1 (σ(2·n²)-σ(n²)) * xⁿ/n ). A195584

Partial sums of A365412. A365442

Square array T(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of e.g.f. cos( sqrt(k) * (exp(x) - 1) ). A357728

Triangle of numbers of permutations eliminating just k cards out of n in game of Mousetrap. A28305

Triangle T₄(n, m), the number of surjective multi-valued functions from {1, 1, 1, 1, 2, 3, ..., n-3} to {1, 2, 3, ..., m} by rows (n >= 1, 1 <= m <= n). A172108