18082121 has 4 divisors (see below), whose sum is σ = 18106644. Its totient is φ = 18057600.

The previous prime is 18082111. The next prime is 18082151. The reversal of 18082121 is 12128081.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3367225 + 14714896 = 1835^2 + 3836^2 .

It is a cyclic number.

It is not a de Polignac number, because 18082121 - 2¹⁰ = 18081097 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 (18082111) 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, 11120 + ... + 12641.

It is an arithmetic number, because the mean of its divisors is an integer number (4526661).

Almost surely, 2^18082121 is an apocalyptic number.

It is an amenable number.

18082121 is a deficient number, since it is larger than the sum of its proper divisors (24523).

18082121 is an equidigital number, since it uses as much as digits as its factorization.

18082121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24522.

The product of its (nonzero) digits is 256, while the sum is 23.

The square root of 18082121 is about 4252.3077263999. The cubic root of 18082121 is about 262.4720865254.

The spelling of 18082121 in words is "eighteen million, eighty-two thousand, one hundred twenty-one".