18197 has 4 divisors (see below), whose sum is σ = 18816. Its totient is φ = 17580.

The previous prime is 18191. The next prime is 18199. The reversal of 18197 is 79181.

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 18197 - 2⁴ = 18181 is a prime.

It is a super-2 number, since 2×18197² = 662261618, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 263 + ... + 324.

It is an arithmetic number, because the mean of its divisors is an integer number (4704).

2¹⁸¹⁹⁷ is an apocalyptic number.

It is an amenable number.

18197 is a deficient number, since it is larger than the sum of its proper divisors (619).

18197 is an equidigital number, since it uses as much as digits as its factorization.

18197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618.

The product of its digits is 504, while the sum is 26.

The square root of 18197 is about 134.8962564343. The cubic root of 18197 is about 26.3026757821.

The spelling of 18197 in words is "eighteen thousand, one hundred ninety-seven".