18000043499991 has 8 divisors (see below), whose sum is σ = 27428637714304. Its totient is φ = 10285739142840.

The previous prime is 18000043499989. The next prime is 18000043500059. The reversal of 18000043499991 is 19999434000081.

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

It is not a de Polignac number, because 18000043499991 - 2¹ = 18000043499989 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 (18000043499941) 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, 428572464265 + ... + 428572464306.

It is an arithmetic number, because the mean of its divisors is an integer number (3428579714288).

Almost surely, 2^{18000043499991} is an apocalyptic number.

18000043499991 is a deficient number, since it is larger than the sum of its proper divisors (9428594214313).

18000043499991 is an equidigital number, since it uses as much as digits as its factorization.

18000043499991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 857144928581.

The product of its (nonzero) digits is 2519424, while the sum is 57.

The spelling of 18000043499991 in words is "eighteen trillion, forty-three million, four hundred ninety-nine thousand, nine hundred ninety-one".