700321

Appears in sequences

• Numbers k such that 4*phi(k) = 3*sigma(k).at n=8A065819
• Composite squarefree numbers that are multiples of the root mean square of their prime factors.at n=27A255356
• Chebyshev pseudoprimes to both base 2 and base 3: composite numbers k such that T(k, 2) == 2 (mod k) and T(k, 3) == 3 (mod k), where T(k, x) is the k-th Chebyshev polynomial of the first kind.at n=25A330208
• Numbers k such that omega(k) = 4 and p^omega(k) < k^(1/4) < lpf(k)^(omega(k)+1) for all primes p | k such that p > lpf(k), where lpf = A020639(k).at n=6A383178