18198320897818 has 8 divisors (see below), whose sum is σ = 27297897454548. Its totient is φ = 9099021746304.

The previous prime is 18198320897747. The next prime is 18198320897819. The reversal of 18198320897818 is 81879802389181.

It can be written as a sum of positive squares in 2 ways, for example, as 17463815334729 + 734505563089 = 4178973^2 + 857033^2 .

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

It is a super-2 number, since 2×18198320897818² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18198320897819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69187221 + ... + 69449752.

Almost surely, 2^{18198320897818} is an apocalyptic number.

18198320897818 is a deficient number, since it is larger than the sum of its proper divisors (9099576556730).

18198320897818 is a wasteful number, since it uses less digits than its factorization.

18198320897818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138702608.

The product of its (nonzero) digits is 111476736, while the sum is 73.

The spelling of 18198320897818 in words is "eighteen trillion, one hundred ninety-eight billion, three hundred twenty million, eight hundred ninety-seven thousand, eight hundred eighteen".