121904

Appears in sequences

• Numbers k such that both k and k+1 are abundant.at n=35A096399
• Composite numbers that are anagrams of the concatenation of their prime factors.at n=25A306474
• Numbers k such that both k and k+1 are Zumkeller numbers (A083207).at n=33A328327
• Numbers k such that each of k and k+1 is either a practical number (A005153) or an almost practical number (A174533).at n=23A387654