Properties of the Number 245

Two Hundred Forty-Five

Basics

Value: 244 → 245 → 246

Parity: odd

Prime: No

Previous Prime: 241

Next Prime: 251

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 5 × 7 ²

Divisors: 1, 5, 7, 35, 49, 245

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 11110101

Octal: 365

Duodecimal: 185

Hexadecimal: f5

Square: 60025

Square Root: 15.652475842498529

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

Primorial base exp-function: digits in primorial base representation of n become the exponents of successive prime factors whose product a(n) is. A276086

The Doudna sequence: write n-1 in binary; power of prime(k) in a(n) is # of 1's that are followed by k-1 0's. A5940

a(0)=1. a(n) = p(A000120(n)) * ∏_{m=1..A000120(n)} p(m)^A163510(n,m), where p(m) is the m-th prime. A163511

Numbers k that divide the (left) concatenation of all numbers <= k written in base 2 (most significant digit on left). A29471

Prime factorization representation of Stern polynomials: a(0) = 1, a(1) = 2, a(2n) = A003961(a(n)), a(2n+1) = a(n)*a(n+1). A260443

Odd numbers of the form p^1+4k * r², where p is prime of the form 1+4m, r > 1, and gcd(p,r) = 1. (Euler's criteria for odd perfect numbers). A228058

Multiples of 5: a(n) = 5·n. A8587

Prime shift array: Square array read by antidiagonals: A(1,col) = 2·col, and for row > 1, A(row,col) = A003961(A(row-1,col)). A246278

Numbers which are the product of a prime and the square of a different prime (p² * q). A54753

Multiples of 7. A8589