145915

Appears in sequences

• Numbers k such that sigma(k) = sigma(k+3).at n=7A015861
• Quasi-Carmichael numbers to base -5: squarefree composites n such that prime p|n ==> p+5|n+5.at n=21A029565
• Composite squarefree numbers n such that p(i)+7 divides n-7, where p(i) are the prime factors of n.at n=17A225717
• Near 2-hyperperfect numbers: numbers k such that sigma(k) - 3*k/2 - 1/2 is a proper divisor of k.at n=23A305616