18147215018 has 4 divisors (see below), whose sum is σ = 27220822530. Its totient is φ = 9073607508.

The previous prime is 18147214997. The next prime is 18147215059. The reversal of 18147215018 is 81051274181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81051274181 = 241 ⋅336312341.

It can be written as a sum of positive squares in only one way, i.e., 12083945329 + 6063269689 = 109927^2 + 77867^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4536803753 + ... + 4536803756.

Almost surely, 2^18147215018 is an apocalyptic number.

18147215018 is a deficient number, since it is larger than the sum of its proper divisors (9073607512).

18147215018 is an equidigital number, since it uses as much as digits as its factorization.

18147215018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9073607511.

The product of its (nonzero) digits is 17920, while the sum is 38.

Adding to 18147215018 its reverse (81051274181), we get a palindrome (99198489199).

The spelling of 18147215018 in words is "eighteen billion, one hundred forty-seven million, two hundred fifteen thousand, eighteen".