999723232991 has 24 divisors (see below), whose sum is σ = 1172338968240. Its totient is φ = 849988339200.

The previous prime is 999723232987. The next prime is 999723232993. The reversal of 999723232991 is 199232327999.

It is not a de Polignac number, because 999723232991 - 2² = 999723232987 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 (999723232993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14993615 + ... + 15060143.

It is an arithmetic number, because the mean of its divisors is an integer number (48847457010).

Almost surely, 2^999723232991 is an apocalyptic number.

999723232991 is a deficient number, since it is larger than the sum of its proper divisors (172615735249).

999723232991 is a wasteful number, since it uses less digits than its factorization.

With its successor (999723232992) it forms a Ruth-Aaron pair, since the sum of their distinct prime factors is the same (69008).

With its successor (999723232992) it forms an eRAP, since the sums of their prime factors are consecutive (69015 and 69016).

999723232991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69015 (or 69008 counting only the distinct ones).

The product of its digits is 29760696, while the sum is 65.

The spelling of 999723232991 in words is "nine hundred ninety-nine billion, seven hundred twenty-three million, two hundred thirty-two thousand, nine hundred ninety-one".