12021131221028 has 24 divisors (see below), whose sum is σ = 21184735655160. Its totient is φ = 5968435500800.

The previous prime is 12021131221009. The next prime is 12021131221037. The reversal of 12021131221028 is 82012213112021.

It can be written as a sum of positive squares in 4 ways, for example, as 8467913761024 + 3553217460004 = 2909968^2 + 1884998^2 .

It is a junction number, because it is equal to n+sod(n) for n = 12021131220988 and 12021131221006.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10176623 + ... + 11296278.

It is an arithmetic number, because the mean of its divisors is an integer number (882697318965).

Almost surely, 2^{12021131221028} is an apocalyptic number.

It is an amenable number.

12021131221028 is a deficient number, since it is larger than the sum of its proper divisors (9163604434132).

12021131221028 is a wasteful number, since it uses less digits than its factorization.

12021131221028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21473887 (or 21473885 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 26.

Adding to 12021131221028 its reverse (82012213112021), we get a palindrome (94033344333049).

The spelling of 12021131221028 in words is "twelve trillion, twenty-one billion, one hundred thirty-one million, two hundred twenty-one thousand, twenty-eight".