18045217 has 4 divisors (see below), whose sum is σ = 18120960. Its totient is φ = 17969476.

The previous prime is 18045199. The next prime is 18045253. The reversal of 18045217 is 71254081.

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: 71254081 = 1789 ⋅39829.

It is a cyclic number.

It is not a de Polignac number, because 18045217 - 2¹¹ = 18043169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18045257) 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, 37513 + ... + 37990.

It is an arithmetic number, because the mean of its divisors is an integer number (4530240).

Almost surely, 2^18045217 is an apocalyptic number.

It is an amenable number.

18045217 is a deficient number, since it is larger than the sum of its proper divisors (75743).

18045217 is an equidigital number, since it uses as much as digits as its factorization.

18045217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75742.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 18045217 is about 4247.9662192630. The cubic root of 18045217 is about 262.2934041875.

Adding to 18045217 its reverse (71254081), we get a palindrome (89299298).

It can be divided in two parts, 1804 and 5217, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 18045217 in words is "eighteen million, forty-five thousand, two hundred seventeen".