390728 has 36 divisors (see below), whose sum is σ = 842715.
Its totient is φ = 169728.
The previous prime is 390727. The next prime is 390737. The reversal of 390728 is 827093.
It is a powerful number, because all its prime factors have an exponent greater than 1
and also an Achilles number because it is not a perfect power.
It can be written as a sum of positive squares in 5 ways, for example, as 158404 + 232324 = 398^2 + 482^2
It is an ABA number since it can be written as A⋅BA, here for A=2, B=442.
It is a Duffinian number.
It is a self number, because there is not a number n which added to its sum of digits gives 390728.
It is not an unprimeable number, because it can be changed into a prime (390721) by changing a digit.
It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 22976 + ... + 22992.
2390728 is an apocalyptic number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 390728
390728 is an abundant number, since it is smaller than the sum of its proper divisors (451987).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
390728 is a wasteful number, since it uses less digits than its factorization.
390728 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 66 (or 32 counting only the distinct ones).
The product of its (nonzero) digits is 3024, while the sum is 29.
The square root of 390728 is about 625.0823945689.
The cubic root of 390728 is about 73.1068679323.
The spelling of 390728 in words is "three hundred ninety thousand, seven hundred twenty-eight".