840003 has 4 divisors (see below), whose sum is σ = 1120008. Its totient is φ = 560000.

The previous prime is 839999. The next prime is 840023. The reversal of 840003 is 300048.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 840003 - 2² = 839999 is a prime.

It is a D-number.

840003 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (840023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 139998 + ... + 140003.

It is an arithmetic number, because the mean of its divisors is an integer number (280002).

2⁸⁴⁰⁰⁰³ is an apocalyptic number.

840003 is a deficient number, since it is larger than the sum of its proper divisors (280005).

840003 is a wasteful number, since it uses less digits than its factorization.

840003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280004.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 840003 is about 916.5167756239. The cubic root of 840003 is about 94.3539919322.

The spelling of 840003 in words is "eight hundred forty thousand, three".