428720 has 40 divisors (see below), whose sum is σ = 1044576. Its totient is φ = 163328.

The previous prime is 428693. The next prime is 428731. The reversal of 428720 is 27824.

428720 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (23).

It is an unprimeable number.

428720 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 7 ways as a sum of consecutive naturals, for example, 1724 + ... + 1956.

2⁴²⁸⁷²⁰ is an apocalyptic number.

428720 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 428720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (522288).

428720 is an abundant number, since it is smaller than the sum of its proper divisors (615856).

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

428720 is a wasteful number, since it uses less digits than its factorization.

428720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 263 counting only the distinct ones).

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

The square root of 428720 is about 654.7671341783. The cubic root of 428720 is about 75.4034553879.

The spelling of 428720 in words is "four hundred twenty-eight thousand, seven hundred twenty".