12321018 has 32 divisors (see below), whose sum is σ = 27720000. Its totient is φ = 4056048.

The previous prime is 12321017. The next prime is 12321041. The reversal of 12321018 is 81012321.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (12321011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3108 + ... + 5856.

It is an arithmetic number, because the mean of its divisors is an integer number (866250).

Almost surely, 2^12321018 is an apocalyptic number.

12321018 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 12321018, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13860000).

12321018 is an abundant number, since it is smaller than the sum of its proper divisors (15398982).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12321018 is a wasteful number, since it uses less digits than its factorization.

12321018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2843 (or 2837 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 12321018 is about 3510.1307667949. The cubic root of 12321018 is about 230.9664312833.

Adding to 12321018 its reverse (81012321), we get a palindrome (93333339).

The spelling of 12321018 in words is "twelve million, three hundred twenty-one thousand, eighteen".