18343321 has 2 divisors, whose sum is σ = 18343322. Its totient is φ = 18343320.

The previous prime is 18343319. The next prime is 18343337. The reversal of 18343321 is 12334381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16281225 + 2062096 = 4035^2 + 1436^2 .

It is a cyclic number.

It is not a de Polignac number, because 18343321 - 2¹ = 18343319 is a prime.

Together with 18343319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18343361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9171660 + 9171661.

It is an arithmetic number, because the mean of its divisors is an integer number (9171661).

Almost surely, 2^18343321 is an apocalyptic number.

It is an amenable number.

18343321 is a deficient number, since it is larger than the sum of its proper divisors (1).

18343321 is an equidigital number, since it uses as much as digits as its factorization.

18343321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 25.

The square root of 18343321 is about 4282.9103422790. The cubic root of 18343321 is about 263.7298708087.

The spelling of 18343321 in words is "eighteen million, three hundred forty-three thousand, three hundred twenty-one".