18103321 has 4 divisors (see below), whose sum is σ = 18116532. Its totient is φ = 18090112.

The previous prime is 18103313. The next prime is 18103331. The reversal of 18103321 is 12330181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12330181 = 101 ⋅122081.

It can be written as a sum of positive squares in 2 ways, for example, as 7080921 + 11022400 = 2661^2 + 3320^2 .

It is a cyclic number.

It is not a de Polignac number, because 18103321 - 2³ = 18103313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18103331) 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, 4276 + ... + 7381.

It is an arithmetic number, because the mean of its divisors is an integer number (4529133).

Almost surely, 2^18103321 is an apocalyptic number.

It is an amenable number.

18103321 is a deficient number, since it is larger than the sum of its proper divisors (13211).

18103321 is a wasteful number, since it uses less digits than its factorization.

18103321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13210.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 18103321 is about 4254.7997602707. The cubic root of 18103321 is about 262.5746230775.

The spelling of 18103321 in words is "eighteen million, one hundred three thousand, three hundred twenty-one".