840143 has 4 divisors (see below), whose sum is σ = 852048. Its totient is φ = 828240.

The previous prime is 840139. The next prime is 840149. The reversal of 840143 is 341048.

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 840143 - 2² = 840139 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 840143.

It is not an unprimeable number, because it can be changed into a prime (840149) 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, 5846 + ... + 5987.

It is an arithmetic number, because the mean of its divisors is an integer number (213012).

2⁸⁴⁰¹⁴³ is an apocalyptic number.

840143 is a deficient number, since it is larger than the sum of its proper divisors (11905).

840143 is a wasteful number, since it uses less digits than its factorization.

840143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11904.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 840143 is about 916.5931485670. The cubic root of 840143 is about 94.3592335108.

The spelling of 840143 in words is "eight hundred forty thousand, one hundred forty-three".