18310018 has 4 divisors (see below), whose sum is σ = 27465030. Its totient is φ = 9155008.

The previous prime is 18310013. The next prime is 18310021. The reversal of 18310018 is 81001381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81001381 = 191 ⋅424091.

It can be written as a sum of positive squares in only one way, i.e., 17665209 + 644809 = 4203^2 + 803^2 .

It is not an unprimeable number, because it can be changed into a prime (18310013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4577503 + ... + 4577506.

Almost surely, 2^18310018 is an apocalyptic number.

18310018 is a deficient number, since it is larger than the sum of its proper divisors (9155012).

18310018 is an equidigital number, since it uses as much as digits as its factorization.

18310018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9155011.

The product of its (nonzero) digits is 192, while the sum is 22.

The square root of 18310018 is about 4279.0206823524. The cubic root of 18310018 is about 263.5701702371.

Adding to 18310018 its reverse (81001381), we get a palindrome (99311399).

It can be divided in two parts, 183 and 10018, that added together give a palindrome (10201).

The spelling of 18310018 in words is "eighteen million, three hundred ten thousand, eighteen".