18117047 has 4 divisors (see below), whose sum is σ = 19510680. Its totient is φ = 16723416.

The previous prime is 18117041. The next prime is 18117101. The reversal of 18117047 is 74071181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74071181 = 311 ⋅238171.

It is a cyclic number.

It is not a de Polignac number, because 18117047 - 2¹⁰ = 18116023 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 (18117041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 696797 + ... + 696822.

It is an arithmetic number, because the mean of its divisors is an integer number (4877670).

Almost surely, 2^18117047 is an apocalyptic number.

18117047 is a deficient number, since it is larger than the sum of its proper divisors (1393633).

18117047 is a wasteful number, since it uses less digits than its factorization.

18117047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1393632.

The product of its (nonzero) digits is 1568, while the sum is 29.

The square root of 18117047 is about 4256.4124565178. The cubic root of 18117047 is about 262.6409679723.

The spelling of 18117047 in words is "eighteen million, one hundred seventeen thousand, forty-seven".