1378841664397 has 2 divisors, whose sum is σ = 1378841664398. Its totient is φ = 1378841664396.

The previous prime is 1378841664337. The next prime is 1378841664407. The reversal of 1378841664397 is 7934661488731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1204141907556 + 174699756841 = 1097334^2 + 417971^2 .

It is a cyclic number.

It is not a de Polignac number, because 1378841664397 - 2¹¹ = 1378841662349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1378841664337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 689420832198 + 689420832199.

It is an arithmetic number, because the mean of its divisors is an integer number (689420832199).

Almost surely, 2^{1378841664397} is an apocalyptic number.

It is an amenable number.

1378841664397 is a deficient number, since it is larger than the sum of its proper divisors (1).

1378841664397 is an equidigital number, since it uses as much as digits as its factorization.

1378841664397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 146313216, while the sum is 67.

The spelling of 1378841664397 in words is "one trillion, three hundred seventy-eight billion, eight hundred forty-one million, six hundred sixty-four thousand, three hundred ninety-seven".