18220303 has 4 divisors (see below), whose sum is σ = 18332248. Its totient is φ = 18108360.

The previous prime is 18220291. The next prime is 18220313. The reversal of 18220303 is 30302281.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18220303 - 2⁵ = 18220271 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18220313) 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, 55728 + ... + 56053.

It is an arithmetic number, because the mean of its divisors is an integer number (4583062).

Almost surely, 2^18220303 is an apocalyptic number.

18220303 is a deficient number, since it is larger than the sum of its proper divisors (111945).

18220303 is a wasteful number, since it uses less digits than its factorization.

18220303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111944.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 18220303 is about 4268.5246865867. The cubic root of 18220303 is about 263.1389869061.

Adding to 18220303 its reverse (30302281), we get a palindrome (48522584).

The spelling of 18220303 in words is "eighteen million, two hundred twenty thousand, three hundred three".