A number n is called an e-perfect number if σ_e(n) = 2n, where σ_e(n) is the sum of the e-Divisors of n. If m is squarefree, then σ_e(m) = m. As a result, if n is e-perfect and m is squarefree with m⊥n, then m n is e-perfect. The first few e-perfect numbers are 36, 180, 252, 396, 468, ... (OEIS A054979). There are no odd e-perfect numbers. The first few primitive e-perfect numbers are 36, 1800, 2700, 17424, ... (OEIS A054980).

e-divisor