18199820181 has 8 divisors (see below), whose sum is σ = 24339740704. Its totient is φ = 12096556560.

The previous prime is 18199820179. The next prime is 18199820189. The reversal of 18199820181 is 18102899181.

It is a happy number.

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

It is not a de Polignac number, because 18199820181 - 2¹ = 18199820179 is a prime.

It is a super-2 number, since 2×18199820181² (a number of 21 digits) contains 22 as substring.

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 18199820181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18199820189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9163066 + ... + 9165051.

It is an arithmetic number, because the mean of its divisors is an integer number (3042467588).

Almost surely, 2^18199820181 is an apocalyptic number.

It is an amenable number.

18199820181 is a deficient number, since it is larger than the sum of its proper divisors (6139920523).

18199820181 is a wasteful number, since it uses less digits than its factorization.

18199820181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18328451.

The product of its (nonzero) digits is 82944, while the sum is 48.

The spelling of 18199820181 in words is "eighteen billion, one hundred ninety-nine million, eight hundred twenty thousand, one hundred eighty-one".