Properties of the Number 20123

Twenty Thousand One Hundred Twenty-Three

Basics

Value: 20122 → 20123 → 20124

Parity: odd

Prime: Yes

Previous Prime: 20117

Next Prime: 20129

Digit Sum: 8

Digital Root: 8

Palindrome: No

Factorization: 20123

Divisors: 1, 20123

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 100111010011011

Octal: 47233

Duodecimal: B78B

Hexadecimal: 4e9b

Square: 404935129

Square Root: 141.8555603422016

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 nonnegative solutions to x² + y² + z² <= n². A604

Primes in A065387 in the order of their appearance. A229264

Fibonacci + Goldbach (dual sequence to A216275). a(1)=5, a(2)=7 and for n>=3, a(n) = g(a(n-1) + a(n-2)), where for m>=3, g(2·m) is the maximal prime p < 2·m such that 2·m - p is prime. A216835

Primes that remain prime through 3 iterations of function f(x) = 2x + 7. A23275

Primes p such that q = 4p² + 1 and r = 4q² + 1 are also prime. A122424

Conjecturally, the largest k such that prime(n)² is the largest squared prime divisor of binomial(2k,k). A239623

a(n+1) is the smallest prime > a(n) such that the digits of a(n) are all (with multiplicity) contained in the digits of a(n+1), with a(1)=2. A242904

Primes p such that p³ - 1 has 8 divisors. A341659

Primes that remain prime through 4 iterations of function f(x) = 2x + 7. A23305

Partition the sequence of natural numbers into groups so that each group product is just >=n! until the group contains only one number which is >= n!; a(n) = the number of such groups. A92980