128947355568761 has 2 divisors, whose sum is σ = 128947355568762. Its totient is φ = 128947355568760.

The previous prime is 128947355568719. The next prime is 128947355568763. The reversal of 128947355568761 is 167865553749821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118545408276736 + 10401947292025 = 10887856^2 + 3225205^2 .

It is an emirp because it is prime and its reverse (167865553749821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128947355568761 - 2⁶ = 128947355568697 is a prime.

Together with 128947355568763, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128947355568763) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64473677784380 + 64473677784381.

It is an arithmetic number, because the mean of its divisors is an integer number (64473677784381).

Almost surely, 2^{128947355568761} is an apocalyptic number.

It is an amenable number.

128947355568761 is a deficient number, since it is larger than the sum of its proper divisors (1).

128947355568761 is an equidigital number, since it uses as much as digits as its factorization.

128947355568761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3048192000, while the sum is 77.

The spelling of 128947355568761 in words is "one hundred twenty-eight trillion, nine hundred forty-seven billion, three hundred fifty-five million, five hundred sixty-eight thousand, seven hundred sixty-one".