420728 has 32 divisors (see below), whose sum is σ = 984960. Its totient is φ = 163680.

The previous prime is 420691. The next prime is 420731. The reversal of 420728 is 827024.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 420728.

It is an unprimeable number.

420728 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 275 + ... + 957.

It is an arithmetic number, because the mean of its divisors is an integer number (30780).

2⁴²⁰⁷²⁸ 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 420728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (492480).

420728 is an abundant number, since it is smaller than the sum of its proper divisors (564232).

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

420728 is a wasteful number, since it uses less digits than its factorization.

420728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707 (or 703 counting only the distinct ones).

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

The square root of 420728 is about 648.6354908575. The cubic root of 420728 is about 74.9319679368.

The spelling of 420728 in words is "four hundred twenty thousand, seven hundred twenty-eight".