18320297 has 4 divisors (see below), whose sum is σ = 18348036. Its totient is φ = 18292560.

The previous prime is 18320261. The next prime is 18320311. The reversal of 18320297 is 79202381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79202381 = 7577 ⋅10453.

It can be written as a sum of positive squares in 2 ways, for example, as 11669056 + 6651241 = 3416^2 + 2579^2 .

It is a cyclic number.

It is not a de Polignac number, because 18320297 - 2⁶ = 18320233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18320227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12854 + ... + 14207.

It is an arithmetic number, because the mean of its divisors is an integer number (4587009).

Almost surely, 2^18320297 is an apocalyptic number.

It is an amenable number.

18320297 is a deficient number, since it is larger than the sum of its proper divisors (27739).

18320297 is an equidigital number, since it uses as much as digits as its factorization.

18320297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27738.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 18320297 is about 4280.2216064125. The cubic root of 18320297 is about 263.6194826038.

The spelling of 18320297 in words is "eighteen million, three hundred twenty thousand, two hundred ninety-seven".