665028 has 108 divisors (see below), whose sum is σ = 2178540. Its totient is φ = 169344.

The previous prime is 665017. The next prime is 665029. The reversal of 665028 is 820566.

665028 is a `hidden beast` number, since 6 + 650 + 2 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 213444 + 451584 = 462^2 + 672^2 .

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 664992 and 665010.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 665028.

It is not an unprimeable number, because it can be changed into a prime (665029) by changing a digit.

665028 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 22918 + ... + 22946.

2⁶⁶⁵⁰²⁸ 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 665028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1089270).

665028 is an abundant number, since it is smaller than the sum of its proper divisors (1513512).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665028 is a wasteful number, since it uses less digits than its factorization.

665028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 665028 is about 815.4924892358. The cubic root of 665028 is about 87.2864123899.

The spelling of 665028 in words is "six hundred sixty-five thousand, twenty-eight".