18117212 has 12 divisors (see below), whose sum is σ = 32152176. Its totient is φ = 8930880.

The previous prime is 18117191. The next prime is 18117227. The reversal of 18117212 is 21271181.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 31613 + ... + 32180.

It is an arithmetic number, because the mean of its divisors is an integer number (2679348).

Almost surely, 2^18117212 is an apocalyptic number.

It is an amenable number.

18117212 is a deficient number, since it is larger than the sum of its proper divisors (14034964).

18117212 is a wasteful number, since it uses less digits than its factorization.

18117212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63868 (or 63866 counting only the distinct ones).

The product of its digits is 224, while the sum is 23.

The square root of 18117212 is about 4256.4318389938. The cubic root of 18117212 is about 262.6417652992.

Adding to 18117212 its reverse (21271181), we get a palindrome (39388393).

The spelling of 18117212 in words is "eighteen million, one hundred seventeen thousand, two hundred twelve".