999993 has 4 divisors (see below), whose sum is σ = 1333328. Its totient is φ = 666660.

The previous prime is 999983. The next prime is 1000003. The reversal of 999993 is 399999.

999993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (999983) and next prime (1000003).

It is not a de Polignac number, because 999993 - 2⁵ = 999961 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 999993.

It is not an unprimeable number, because it can be changed into a prime (999953) 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, 166663 + ... + 166668.

It is an arithmetic number, because the mean of its divisors is an integer number (333332).

2⁹⁹⁹⁹⁹³ is an apocalyptic number.

It is an amenable number.

999993 is a deficient number, since it is larger than the sum of its proper divisors (333335).

999993 is a wasteful number, since it uses less digits than its factorization.

999993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333334.

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

The square root of 999993 is about 999.9964999939. The cubic root of 999993 is about 99.9997666661. Note that the first 3 decimals are identical.

The spelling of 999993 in words is "nine hundred ninety-nine thousand, nine hundred ninety-three".