18891974800321 has 24 divisors (see below), whose sum is σ = 23269577564160. Its totient is φ = 15240276519552.

The previous prime is 18891974800297. The next prime is 18891974800367. The reversal of 18891974800321 is 12300847919881.

It is not a de Polignac number, because 18891974800321 - 2⁹ = 18891974799809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18891974800321.

It is not an unprimeable number, because it can be changed into a prime (18891974804321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46765920 + ... + 47168158.

It is an arithmetic number, because the mean of its divisors is an integer number (969565731840).

Almost surely, 2^{18891974800321} is an apocalyptic number.

It is an amenable number.

18891974800321 is a deficient number, since it is larger than the sum of its proper divisors (4377602763839).

18891974800321 is a wasteful number, since it uses less digits than its factorization.

18891974800321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458653 (or 458646 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 61.

The spelling of 18891974800321 in words is "eighteen trillion, eight hundred ninety-one billion, nine hundred seventy-four million, eight hundred thousand, three hundred twenty-one".