999986 has 8 divisors (see below), whose sum is σ = 1615404. Its totient is φ = 461520.

The previous prime is 999983. The next prime is 1000003. The reversal of 999986 is 689999.

It can be written as a sum of positive squares in 2 ways, for example, as 866761 + 133225 = 931^2 + 365^2 .

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

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (999983) 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, 19205 + ... + 19256.

2⁹⁹⁹⁹⁸⁶ is an apocalyptic number.

999986 is a deficient number, since it is larger than the sum of its proper divisors (615418).

999986 is a wasteful number, since it uses less digits than its factorization.

999986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38476.

The product of its digits is 314928, while the sum is 50.

The square root of 999986 is about 999.9929999755. The cubic root of 999986 is about 99.9995333312. Note that the first 3 decimals are identical.

The spelling of 999986 in words is "nine hundred ninety-nine thousand, nine hundred eighty-six".