999959823 has 16 divisors (see below), whose sum is σ = 1499714400. Its totient is φ = 666638424.

The previous prime is 999959803. The next prime is 999959867. The reversal of 999959823 is 328959999.

It is not a de Polignac number, because 999959823 - 2²⁹ = 463088911 is a prime.

It is a super-2 number, since 2×999959823² = 1999839295228382658, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999959803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 226428 + ... + 230801.

It is an arithmetic number, because the mean of its divisors is an integer number (93732150).

Almost surely, 2^999959823 is an apocalyptic number.

999959823 is a deficient number, since it is larger than the sum of its proper divisors (499754577).

999959823 is an frugal number, since it uses more digits than its factorization.

999959823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457250 (or 457232 counting only the distinct ones).

The product of its digits is 14171760, while the sum is 63.

The square root of 999959823 is about 31622.1413411553. The cubic root of 999959823 is about 999.9866074873.

The spelling of 999959823 in words is "nine hundred ninety-nine million, nine hundred fifty-nine thousand, eight hundred twenty-three".