42728 has 24 divisors (see below), whose sum is σ = 94050. Its totient is φ = 18144.

The previous prime is 42727. The next prime is 42737. The reversal of 42728 is 82724.

42728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 33124 + 9604 = 182^2 + 98^2 .

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (42727) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 338 + ... + 446.

2⁴²⁷²⁸ 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 42728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47025).

42728 is an abundant number, since it is smaller than the sum of its proper divisors (51322).

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

42728 is a wasteful number, since it uses less digits than its factorization.

42728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 118 counting only the distinct ones).

The product of its digits is 896, while the sum is 23.

The square root of 42728 is about 206.7075228433. The cubic root of 42728 is about 34.9599541984.

The spelling of 42728 in words is "forty-two thousand, seven hundred twenty-eight".