999939 has 8 divisors (see below), whose sum is σ = 1342800. Its totient is φ = 661856.

The previous prime is 999931. The next prime is 999953. The reversal of 999939 is 939999.

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

It is a cyclic number.

It is not a de Polignac number, because 999939 - 2³ = 999931 is a prime.

It is not an unprimeable number, because it can be changed into a prime (999931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 672 + ... + 1565.

It is an arithmetic number, because the mean of its divisors is an integer number (167850).

2⁹⁹⁹⁹³⁹ is an apocalyptic number.

999939 is a deficient number, since it is larger than the sum of its proper divisors (342861).

999939 is a wasteful number, since it uses less digits than its factorization.

999939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2389.

The product of its digits is 177147, while the sum is 48.

The square root of 999939 is about 999.9694995349. The cubic root of 999939 is about 99.9979666253.

The spelling of 999939 in words is "nine hundred ninety-nine thousand, nine hundred thirty-nine".