12021228 has 18 divisors (see below), whose sum is σ = 30387084. Its totient is φ = 4007064.

The previous prime is 12021187. The next prime is 12021259. The reversal of 12021228 is 82212021.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (18).

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

It is a self number, because there is not a number n which added to its sum of digits gives 12021228.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 166926 + ... + 166997.

Almost surely, 2^12021228 is an apocalyptic number.

12021228 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

12021228 is an abundant number, since it is smaller than the sum of its proper divisors (18365856).

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

12021228 is a wasteful number, since it uses less digits than its factorization.

12021228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333933 (or 333928 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 12021228 is about 3467.1642591605. The cubic root of 12021228 is about 229.0777689502.

Adding to 12021228 its reverse (82212021), we get a palindrome (94233249).

The spelling of 12021228 in words is "twelve million, twenty-one thousand, two hundred twenty-eight".