4004028 has 36 divisors (see below), whose sum is σ = 11567920. Its totient is φ = 1143936.

The previous prime is 4004023. The next prime is 4004057. The reversal of 4004028 is 8204004.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a self number, because there is not a number n which added to its sum of digits gives 4004028.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4004023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7693 + ... + 8196.

Almost surely, 2^4004028 is an apocalyptic number.

It is an amenable number.

4004028 is an abundant number, since it is smaller than the sum of its proper divisors (7563892).

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

4004028 is a wasteful number, since it uses less digits than its factorization.

4004028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15906 (or 15901 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 4004028 is about 2001.0067466153. The cubic root of 4004028 is about 158.7933710832.

The spelling of 4004028 in words is "four million, four thousand, twenty-eight".