840004 has 24 divisors (see below), whose sum is σ = 1699488. Its totient is φ = 359040.

The previous prime is 839999. The next prime is 840023. The reversal of 840004 is 400048.

It is a self number, because there is not a number n which added to its sum of digits gives 840004.

It is an unprimeable number.

840004 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, 187 + ... + 1309.

It is an arithmetic number, because the mean of its divisors is an integer number (70812).

2⁸⁴⁰⁰⁰⁴ is an apocalyptic number.

It is an amenable number.

840004 is an abundant number, since it is smaller than the sum of its proper divisors (859484).

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

840004 is a wasteful number, since it uses less digits than its factorization.

840004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1155 (or 1153 counting only the distinct ones).

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

The square root of 840004 is about 916.5173211675. The cubic root of 840004 is about 94.3540293742.

The spelling of 840004 in words is "eight hundred forty thousand, four".