18218297 has 4 divisors (see below), whose sum is σ = 18806016. Its totient is φ = 17630580.

The previous prime is 18218287. The next prime is 18218311. The reversal of 18218297 is 79281281.

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, and also an emirpimes, since its reverse is a distinct semiprime: 79281281 = 19 ⋅4172699.

It is a cyclic number.

It is not a de Polignac number, because 18218297 - 2⁸ = 18218041 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18218297.

It is not an unprimeable number, because it can be changed into a prime (18218257) 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, 293813 + ... + 293874.

It is an arithmetic number, because the mean of its divisors is an integer number (4701504).

Almost surely, 2^18218297 is an apocalyptic number.

It is an amenable number.

18218297 is a deficient number, since it is larger than the sum of its proper divisors (587719).

18218297 is an equidigital number, since it uses as much as digits as its factorization.

18218297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587718.

The product of its digits is 16128, while the sum is 38.

The square root of 18218297 is about 4268.2897043195. The cubic root of 18218297 is about 263.1293296173.

The spelling of 18218297 in words is "eighteen million, two hundred eighteen thousand, two hundred ninety-seven".