18386943 has 8 divisors (see below), whose sum is σ = 24538800. Its totient is φ = 12246528.

The previous prime is 18386923. The next prime is 18386947. The reversal of 18386943 is 34968381.

It is a happy number.

It is a Cunningham number, because it is equal to 4288²-1.

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

It is not a de Polignac number, because 18386943 - 2¹⁰ = 18385919 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a plaindrome in base 16.

It is a zygodrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 18386895 and 18386904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18386947) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2143 + ... + 6431.

It is an arithmetic number, because the mean of its divisors is an integer number (3067350).

Almost surely, 2^18386943 is an apocalyptic number.

18386943 is a deficient number, since it is larger than the sum of its proper divisors (6151857).

18386943 is a wasteful number, since it uses less digits than its factorization.

18386943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5721.

The product of its digits is 124416, while the sum is 42.

The square root of 18386943 is about 4287.9998833955. Note that the first 3 decimals coincide. The cubic root of 18386943 is about 263.9387627708.

The spelling of 18386943 in words is "eighteen million, three hundred eighty-six thousand, nine hundred forty-three".