999968 has 12 divisors (see below), whose sum is σ = 1968750. Its totient is φ = 499968.

The previous prime is 999961. The next prime is 999979. The reversal of 999968 is 869999.

It can be written as a sum of positive squares in only one way, i.e., 795664 + 204304 = 892^2 + 452^2 .

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (999961) by changing a digit.

999968 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 as a sum of consecutive naturals, namely, 15593 + ... + 15656.

2⁹⁹⁹⁹⁶⁸ is an apocalyptic number.

It is an amenable number.

999968 is a deficient number, since it is larger than the sum of its proper divisors (968782).

999968 is a wasteful number, since it uses less digits than its factorization.

999968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31259 (or 31251 counting only the distinct ones).

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

The square root of 999968 is about 999.9839998720. The cubic root of 999968 is about 99.9989333220.

The spelling of 999968 in words is "nine hundred ninety-nine thousand, nine hundred sixty-eight".