12221202120821 has 2 divisors, whose sum is σ = 12221202120822. Its totient is φ = 12221202120820.

The previous prime is 12221202120719. The next prime is 12221202120877. The reversal of 12221202120821 is 12802120212221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8261520009796 + 3959682111025 = 2874286^2 + 1989895^2 .

It is a cyclic number.

It is not a de Polignac number, because 12221202120821 - 2²² = 12221197926517 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12221205120821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6110601060410 + 6110601060411.

It is an arithmetic number, because the mean of its divisors is an integer number (6110601060411).

Almost surely, 2^{12221202120821} is an apocalyptic number.

It is an amenable number.

12221202120821 is a deficient number, since it is larger than the sum of its proper divisors (1).

12221202120821 is an equidigital number, since it uses as much as digits as its factorization.

12221202120821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1024, while the sum is 26.

The spelling of 12221202120821 in words is "twelve trillion, two hundred twenty-one billion, two hundred two million, one hundred twenty thousand, eight hundred twenty-one".