18020306 has 12 divisors (see below), whose sum is σ = 28714938. Its totient is φ = 8479872.

The previous prime is 18020267. The next prime is 18020309. The reversal of 18020306 is 60302081.

It can be written as a sum of positive squares in 3 ways, for example, as 17986081 + 34225 = 4241^2 + 185^2 .

It is not an unprimeable number, because it can be changed into a prime (18020309) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 15011 + ... + 16166.

Almost surely, 2^18020306 is an apocalyptic number.

18020306 is a deficient number, since it is larger than the sum of its proper divisors (10694632).

18020306 is a wasteful number, since it uses less digits than its factorization.

18020306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31213 (or 31196 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 18020306 is about 4245.0330976330. The cubic root of 18020306 is about 262.1726519687.

Adding to 18020306 its reverse (60302081), we get a palindrome (78322387).

The spelling of 18020306 in words is "eighteen million, twenty thousand, three hundred six".