18321197 has 4 divisors (see below), whose sum is σ = 18414396. Its totient is φ = 18228000.

The previous prime is 18321169. The next prime is 18321203. The reversal of 18321197 is 79112381.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17023876 + 1297321 = 4126^2 + 1139^2 .

It is a cyclic number.

It is not a de Polignac number, because 18321197 - 2¹⁴ = 18304813 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 (18323197) 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, 46304 + ... + 46697.

It is an arithmetic number, because the mean of its divisors is an integer number (4603599).

Almost surely, 2^18321197 is an apocalyptic number.

It is an amenable number.

18321197 is a deficient number, since it is larger than the sum of its proper divisors (93199).

18321197 is an equidigital number, since it uses as much as digits as its factorization.

18321197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93198.

The product of its digits is 3024, while the sum is 32.

The square root of 18321197 is about 4280.3267398646. The cubic root of 18321197 is about 263.6237993760.

The spelling of 18321197 in words is "eighteen million, three hundred twenty-one thousand, one hundred ninety-seven".