18143121 has 4 divisors (see below), whose sum is σ = 24190832. Its totient is φ = 12095412.

The previous prime is 18143101. The next prime is 18143123. The reversal of 18143121 is 12134181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 18143121 - 2⁵ = 18143089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18143123) 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, 3023851 + ... + 3023856.

It is an arithmetic number, because the mean of its divisors is an integer number (6047708).

Almost surely, 2^18143121 is an apocalyptic number.

It is an amenable number.

18143121 is a deficient number, since it is larger than the sum of its proper divisors (6047711).

18143121 is an equidigital number, since it uses as much as digits as its factorization.

18143121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6047710.

The product of its digits is 192, while the sum is 21.

The square root of 18143121 is about 4259.4742633334. The cubic root of 18143121 is about 262.7669049415.

The spelling of 18143121 in words is "eighteen million, one hundred forty-three thousand, one hundred twenty-one".