12021105521 has 2 divisors, whose sum is σ = 12021105522. Its totient is φ = 12021105520.

The previous prime is 12021105493. The next prime is 12021105527. The reversal of 12021105521 is 12550112021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7031661025 + 4989444496 = 83855^2 + 70636^2 .

It is a cyclic number.

It is not a de Polignac number, because 12021105521 - 2¹⁸ = 12020843377 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12021105493 and 12021105502.

It is not a weakly prime, because it can be changed into another prime (12021105527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6010552760 + 6010552761.

It is an arithmetic number, because the mean of its divisors is an integer number (6010552761).

Almost surely, 2^12021105521 is an apocalyptic number.

It is an amenable number.

12021105521 is a deficient number, since it is larger than the sum of its proper divisors (1).

12021105521 is an equidigital number, since it uses as much as digits as its factorization.

12021105521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 200, while the sum is 20.

Adding to 12021105521 its reverse (12550112021), we get a palindrome (24571217542).

The spelling of 12021105521 in words is "twelve billion, twenty-one million, one hundred five thousand, five hundred twenty-one".