18489197 has 2 divisors, whose sum is σ = 18489198. Its totient is φ = 18489196.

The previous prime is 18489193. The next prime is 18489199. The reversal of 18489197 is 79198481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12432676 + 6056521 = 3526^2 + 2461^2 .

It is a cyclic number.

It is not a de Polignac number, because 18489197 - 2² = 18489193 is a prime.

Together with 18489199, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18489193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9244598 + 9244599.

It is an arithmetic number, because the mean of its divisors is an integer number (9244599).

Almost surely, 2^18489197 is an apocalyptic number.

It is an amenable number.

18489197 is a deficient number, since it is larger than the sum of its proper divisors (1).

18489197 is an equidigital number, since it uses as much as digits as its factorization.

18489197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 47.

The square root of 18489197 is about 4299.9066268932. The cubic root of 18489197 is about 264.4271332042.

The spelling of 18489197 in words is "eighteen million, four hundred eighty-nine thousand, one hundred ninety-seven".