18071321 has 8 divisors (see below), whose sum is σ = 18814080. Its totient is φ = 17336592.

The previous prime is 18071297. The next prime is 18071351. The reversal of 18071321 is 12317081.

It is a happy number.

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 18071321 - 2⁶ = 18071257 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18071351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2816 + ... + 6638.

It is an arithmetic number, because the mean of its divisors is an integer number (2351760).

Almost surely, 2^18071321 is an apocalyptic number.

It is an amenable number.

18071321 is a deficient number, since it is larger than the sum of its proper divisors (742759).

18071321 is a wasteful number, since it uses less digits than its factorization.

18071321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4015.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 18071321 is about 4251.0376380362. The cubic root of 18071321 is about 262.4198201074.

It can be divided in two parts, 180713 and 21, that multiplied together give a palindrome (3794973).

The spelling of 18071321 in words is "eighteen million, seventy-one thousand, three hundred twenty-one".