12978206221 has 2 divisors, whose sum is σ = 12978206222. Its totient is φ = 12978206220.

The previous prime is 12978206201. The next prime is 12978206233. The reversal of 12978206221 is 12260287921.

12978206221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10585528996 + 2392677225 = 102886^2 + 48915^2 .

It is a cyclic number.

It is not a de Polignac number, because 12978206221 - 2¹³ = 12978198029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12978206201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6489103110 + 6489103111.

It is an arithmetic number, because the mean of its divisors is an integer number (6489103111).

Almost surely, 2^12978206221 is an apocalyptic number.

It is an amenable number.

12978206221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12978206221 is an equidigital number, since it uses as much as digits as its factorization.

12978206221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 40.

The spelling of 12978206221 in words is "twelve billion, nine hundred seventy-eight million, two hundred six thousand, two hundred twenty-one".