18291091938391 has 8 divisors (see below), whose sum is σ = 19254156974000. Its totient is φ = 17328064501440.

The previous prime is 18291091938307. The next prime is 18291091938403. The reversal of 18291091938391 is 19383919019281.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 18291091938391 - 2¹⁷ = 18291091807319 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 (18291091932391) 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, 8398350 + ... + 10349611.

It is an arithmetic number, because the mean of its divisors is an integer number (2406769621750).

Almost surely, 2^{18291091938391} is an apocalyptic number.

18291091938391 is a deficient number, since it is larger than the sum of its proper divisors (963065035609).

18291091938391 is a wasteful number, since it uses less digits than its factorization.

18291091938391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18799329.

The product of its (nonzero) digits is 7558272, while the sum is 64.

The spelling of 18291091938391 in words is "eighteen trillion, two hundred ninety-one billion, ninety-one million, nine hundred thirty-eight thousand, three hundred ninety-one".