18518370197 has 4 divisors (see below), whose sum is σ = 19493021280. Its totient is φ = 17543719116.

The previous prime is 18518370193. The next prime is 18518370203. The reversal of 18518370197 is 79107381581.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18518370197 - 2² = 18518370193 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18518370191) 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, 487325513 + ... + 487325550.

It is an arithmetic number, because the mean of its divisors is an integer number (4873255320).

Almost surely, 2^18518370197 is an apocalyptic number.

It is an amenable number.

18518370197 is a deficient number, since it is larger than the sum of its proper divisors (974651083).

18518370197 is an equidigital number, since it uses as much as digits as its factorization.

18518370197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 974651082.

The product of its (nonzero) digits is 423360, while the sum is 50.

The spelling of 18518370197 in words is "eighteen billion, five hundred eighteen million, three hundred seventy thousand, one hundred ninety-seven".