12978222077 has 2 divisors, whose sum is σ = 12978222078. Its totient is φ = 12978222076.

The previous prime is 12978222017. The next prime is 12978222097. The reversal of 12978222077 is 77022287921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12572239876 + 405982201 = 112126^2 + 20149^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12978222077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12978222017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6489111038 + 6489111039.

It is an arithmetic number, because the mean of its divisors is an integer number (6489111039).

Almost surely, 2^12978222077 is an apocalyptic number.

It is an amenable number.

12978222077 is a deficient number, since it is larger than the sum of its proper divisors (1).

12978222077 is an equidigital number, since it uses as much as digits as its factorization.

12978222077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 395136, while the sum is 47.

The spelling of 12978222077 in words is "twelve billion, nine hundred seventy-eight million, two hundred twenty-two thousand, seventy-seven".