18020091321 has 24 divisors (see below), whose sum is σ = 27447781920. Its totient is φ = 11360834496.

The previous prime is 18020091317. The next prime is 18020091337. The reversal of 18020091321 is 12319002081.

It is not a de Polignac number, because 18020091321 - 2² = 18020091317 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18020091361) 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, 2685 + ... + 189861.

It is an arithmetic number, because the mean of its divisors is an integer number (1143657580).

Almost surely, 2^18020091321 is an apocalyptic number.

It is an amenable number.

18020091321 is a deficient number, since it is larger than the sum of its proper divisors (9427690599).

18020091321 is a wasteful number, since it uses less digits than its factorization.

18020091321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187765 (or 187762 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The spelling of 18020091321 in words is "eighteen billion, twenty million, ninety-one thousand, three hundred twenty-one".