18646 has 4 divisors (see below), whose sum is σ = 27972. Its totient is φ = 9322.

The previous prime is 18637. The next prime is 18661. The reversal of 18646 is 64681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 64681 = 71 ⋅911.

It is a nialpdrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 18646.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4660 + ... + 4663.

It is an arithmetic number, because the mean of its divisors is an integer number (6993).

2¹⁸⁶⁴⁶ is an apocalyptic number.

18646 is a deficient number, since it is larger than the sum of its proper divisors (9326).

18646 is an equidigital number, since it uses as much as digits as its factorization.

18646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9325.

The product of its digits is 1152, while the sum is 25.

The square root of 18646 is about 136.5503570116. The cubic root of 18646 is about 26.5172546936.

It can be divided in two parts, 186 and 46, that added together give a palindrome (232).

The spelling of 18646 in words is "eighteen thousand, six hundred forty-six".