1816321 has 8 divisors (see below), whose sum is σ = 2019584. Its totient is φ = 1622160.

The previous prime is 1816301. The next prime is 1816337. The reversal of 1816321 is 1236181.

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

It is a cyclic number.

It is not a de Polignac number, because 1816321 - 2⁷ = 1816193 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1816292 and 1816301.

It is not an unprimeable number, because it can be changed into a prime (1816301) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1851 + ... + 2656.

It is an arithmetic number, because the mean of its divisors is an integer number (252448).

2^1816321 is an apocalyptic number.

It is an amenable number.

1816321 is a deficient number, since it is larger than the sum of its proper divisors (203263).

1816321 is a wasteful number, since it uses less digits than its factorization.

1816321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4551.

The product of its digits is 288, while the sum is 22.

The square root of 1816321 is about 1347.7095384392. The cubic root of 1816321 is about 122.0105921109.

The spelling of 1816321 in words is "one million, eight hundred sixteen thousand, three hundred twenty-one".