999858 has 8 divisors (see below), whose sum is σ = 1999728. Its totient is φ = 333284.

The previous prime is 999853. The next prime is 999863. The reversal of 999858 is 858999.

999858 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (999853) and next prime (999863).

It is a sphenic number, since it is the product of 3 distinct primes.

999858 is an admirable number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 999858.

It is not an unprimeable number, because it can be changed into a prime (999853) 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, 83316 + ... + 83327.

It is an arithmetic number, because the mean of its divisors is an integer number (249966).

2⁹⁹⁹⁸⁵⁸ is an apocalyptic number.

999858 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

999858 is a wasteful number, since it uses less digits than its factorization.

999858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166648.

The product of its digits is 233280, while the sum is 48.

The square root of 999858 is about 999.9289974793. The cubic root of 999858 is about 99.9952664426.

The spelling of 999858 in words is "nine hundred ninety-nine thousand, eight hundred fifty-eight".