420028 has 18 divisors (see below), whose sum is σ = 855456. Its totient is φ = 179928.

The previous prime is 420001. The next prime is 420029. The reversal of 420028 is 820024.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 419993 and 420020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420029) by changing a digit.

420028 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 5 ways as a sum of consecutive naturals, for example, 876 + ... + 1267.

2⁴²⁰⁰²⁸ is an apocalyptic number.

It is an amenable number.

420028 is an abundant number, since it is smaller than the sum of its proper divisors (435428).

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

420028 is a wasteful number, since it uses less digits than its factorization.

420028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2161 (or 2152 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 420028 is about 648.0956719498. The cubic root of 420028 is about 74.8903880291.

The spelling of 420028 in words is "four hundred twenty thousand, twenty-eight".