18331320121 has 8 divisors (see below), whose sum is σ = 18660067200. Its totient is φ = 18005301600.

The previous prime is 18331320083. The next prime is 18331320169. The reversal of 18331320121 is 12102313381.

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 18331320121 - 2⁹ = 18331319609 is a prime.

It is a super-3 number, since 3×18331320121³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18331320221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 668581 + ... + 695458.

It is an arithmetic number, because the mean of its divisors is an integer number (2332508400).

Almost surely, 2^18331320121 is an apocalyptic number.

It is an amenable number.

18331320121 is a deficient number, since it is larger than the sum of its proper divisors (328747079).

18331320121 is a wasteful number, since it uses less digits than its factorization.

18331320121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1364279.

The product of its (nonzero) digits is 864, while the sum is 25.

The spelling of 18331320121 in words is "eighteen billion, three hundred thirty-one million, three hundred twenty thousand, one hundred twenty-one".