12213138 has 64 divisors (see below), whose sum is σ = 29859840. Its totient is φ = 3254592.

The previous prime is 12213137. The next prime is 12213167. The reversal of 12213138 is 83131221.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12213137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45268 + ... + 45536.

It is an arithmetic number, because the mean of its divisors is an integer number (466560).

Almost surely, 2^12213138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12213138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14929920).

12213138 is an abundant number, since it is smaller than the sum of its proper divisors (17646702).

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

12213138 is a wasteful number, since it uses less digits than its factorization.

12213138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351.

The product of its digits is 288, while the sum is 21.

The square root of 12213138 is about 3494.7300324918. The cubic root of 12213138 is about 230.2903579281.

Adding to 12213138 its reverse (83131221), we get a palindrome (95344359).

The spelling of 12213138 in words is "twelve million, two hundred thirteen thousand, one hundred thirty-eight".