999688 has 32 divisors (see below), whose sum is σ = 2016000. Its totient is φ = 463680.

The previous prime is 999683. The next prime is 999721. The reversal of 999688 is 886999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7123 + ... + 7261.

It is an arithmetic number, because the mean of its divisors is an integer number (63000).

2⁹⁹⁹⁶⁸⁸ is an apocalyptic number.

It is an amenable number.

999688 is an abundant number, since it is smaller than the sum of its proper divisors (1016312).

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

999688 is a wasteful number, since it uses less digits than its factorization.

999688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205 (or 201 counting only the distinct ones).

The product of its digits is 279936, while the sum is 49.

The square root of 999688 is about 999.8439878301. The cubic root of 999688 is about 99.9895989182.

The spelling of 999688 in words is "nine hundred ninety-nine thousand, six hundred eighty-eight".