18117938 has 8 divisors (see below), whose sum is σ = 27911532. Its totient is φ = 8814096.

The previous prime is 18117923. The next prime is 18117959. The reversal of 18117938 is 83971181.

It can be written as a sum of positive squares in 2 ways, for example, as 18088009 + 29929 = 4253^2 + 173^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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, 122345 + ... + 122492.

Almost surely, 2^18117938 is an apocalyptic number.

18117938 is a deficient number, since it is larger than the sum of its proper divisors (9793594).

18117938 is a wasteful number, since it uses less digits than its factorization.

18117938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244876.

The product of its digits is 12096, while the sum is 38.

The square root of 18117938 is about 4256.5171208395. The cubic root of 18117938 is about 262.6452734802.

The spelling of 18117938 in words is "eighteen million, one hundred seventeen thousand, nine hundred thirty-eight".