128127545336521 has 2 divisors, whose sum is σ = 128127545336522. Its totient is φ = 128127545336520.

The previous prime is 128127545336513. The next prime is 128127545336563. The reversal of 128127545336521 is 125633545721821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 126688418804025 + 1439126532496 = 11255595^2 + 1199636^2 .

It is a cyclic number.

It is not a de Polignac number, because 128127545336521 - 2³ = 128127545336513 is a prime.

It is not a weakly prime, because it can be changed into another prime (128124545336521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64063772668260 + 64063772668261.

It is an arithmetic number, because the mean of its divisors is an integer number (64063772668261).

Almost surely, 2^{128127545336521} is an apocalyptic number.

It is an amenable number.

128127545336521 is a deficient number, since it is larger than the sum of its proper divisors (1).

128127545336521 is an equidigital number, since it uses as much as digits as its factorization.

128127545336521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096000, while the sum is 55.

The spelling of 128127545336521 in words is "one hundred twenty-eight trillion, one hundred twenty-seven billion, five hundred forty-five million, three hundred thirty-six thousand, five hundred twenty-one".