421128 has 24 divisors (see below), whose sum is σ = 1140750. Its totient is φ = 140352.

The previous prime is 421123. The next prime is 421133. The reversal of 421128 is 821124.

It is an interprime number because it is at equal distance from previous prime (421123) and next prime (421133).

It can be written as a sum of positive squares in only one way, i.e., 381924 + 39204 = 618^2 + 198^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (18).

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

It is a self number, because there is not a number n which added to its sum of digits gives 421128.

It is not an unprimeable number, because it can be changed into a prime (421121) by changing a digit.

421128 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, 2853 + ... + 2996.

2⁴²¹¹²⁸ is an apocalyptic number.

It is an amenable number.

421128 is an abundant number, since it is smaller than the sum of its proper divisors (719622).

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

421128 is a wasteful number, since it uses less digits than its factorization.

421128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5861 (or 5854 counting only the distinct ones).

The product of its digits is 128, while the sum is 18.

The square root of 421128 is about 648.9437571932. The cubic root of 421128 is about 74.9557071804.

The spelling of 421128 in words is "four hundred twenty-one thousand, one hundred twenty-eight".