12213128 has 8 divisors (see below), whose sum is σ = 22899630. Its totient is φ = 6106560.

The previous prime is 12213127. The next prime is 12213137. The reversal of 12213128 is 82131221.

12213128 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 12124324 + 88804 = 3482^2 + 298^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12213127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 763313 + ... + 763328.

Almost surely, 2^12213128 is an apocalyptic number.

It is an amenable number.

12213128 is a deficient number, since it is larger than the sum of its proper divisors (10686502).

12213128 is a wasteful number, since it uses less digits than its factorization.

12213128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1526647 (or 1526643 counting only the distinct ones).

The product of its digits is 192, while the sum is 20.

The square root of 12213128 is about 3494.7286017658. The cubic root of 12213128 is about 230.2902950749.

Adding to 12213128 its reverse (82131221), we get a palindrome (94344349).

The spelling of 12213128 in words is "twelve million, two hundred thirteen thousand, one hundred twenty-eight".