18863321 has 4 divisors (see below), whose sum is σ = 19323444. Its totient is φ = 18403200.

The previous prime is 18863297. The next prime is 18863329. The reversal of 18863321 is 12336881.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12336881 = 191 ⋅64591.

It can be written as a sum of positive squares in 2 ways, for example, as 2371600 + 16491721 = 1540^2 + 4061^2 .

It is a cyclic number.

It is not a de Polignac number, because 18863321 - 2¹⁴ = 18846937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18863329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 230000 + ... + 230081.

It is an arithmetic number, because the mean of its divisors is an integer number (4830861).

Almost surely, 2^18863321 is an apocalyptic number.

It is an amenable number.

18863321 is a deficient number, since it is larger than the sum of its proper divisors (460123).

18863321 is an equidigital number, since it uses as much as digits as its factorization.

18863321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460122.

The product of its digits is 6912, while the sum is 32.

The square root of 18863321 is about 4343.1924894022. The cubic root of 18863321 is about 266.1987744838.

The spelling of 18863321 in words is "eighteen million, eight hundred sixty-three thousand, three hundred twenty-one".