999999823 has 6 divisors (see below), whose sum is σ = 1062283856. Its totient is φ = 941176032.

The previous prime is 999999797. The next prime is 999999883. The reversal of 999999823 is 328999999.

It is a happy number.

It is not a de Polignac number, because 999999823 - 2²¹ = 997902671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999999883) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1729815 + ... + 1730392.

Almost surely, 2^999999823 is an apocalyptic number.

999999823 is a deficient number, since it is larger than the sum of its proper divisors (62284033).

999999823 is a wasteful number, since it uses less digits than its factorization.

999999823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3460241 (or 3460224 counting only the distinct ones).

The product of its digits is 25509168, while the sum is 67.

The square root of 999999823 is about 31622.7738030679. The cubic root of 999999823 is about 999.9999410000. Note that the first 4 decimals are identical.

The spelling of 999999823 in words is "nine hundred ninety-nine million, nine hundred ninety-nine thousand, eight hundred twenty-three".