18102011 has 4 divisors (see below), whose sum is σ = 18523032. Its totient is φ = 17680992.

The previous prime is 18101971. The next prime is 18102013. The reversal of 18102011 is 11020181.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18102011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18102013) 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, 210446 + ... + 210531.

It is an arithmetic number, because the mean of its divisors is an integer number (4630758).

Almost surely, 2^18102011 is an apocalyptic number.

18102011 is a deficient number, since it is larger than the sum of its proper divisors (421021).

18102011 is an equidigital number, since it uses as much as digits as its factorization.

18102011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421020.

The product of its (nonzero) digits is 16, while the sum is 14.

The square root of 18102011 is about 4254.6458136959. The cubic root of 18102011 is about 262.5682894136.

Adding to 18102011 its reverse (11020181), we get a palindrome (29122192).

The spelling of 18102011 in words is "eighteen million, one hundred two thousand, eleven".