128756954605481 has 2 divisors, whose sum is σ = 128756954605482. Its totient is φ = 128756954605480.

The previous prime is 128756954605469. The next prime is 128756954605501. The reversal of 128756954605481 is 184506459657821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128300566536256 + 456388069225 = 11326984^2 + 675565^2 .

It is a cyclic number.

It is not a de Polignac number, because 128756954605481 - 2³⁴ = 128739774736297 is a prime.

It is a super-2 number, since 2×128756954605481² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (128756954605421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64378477302740 + 64378477302741.

It is an arithmetic number, because the mean of its divisors is an integer number (64378477302741).

Almost surely, 2^{128756954605481} is an apocalyptic number.

It is an amenable number.

128756954605481 is a deficient number, since it is larger than the sum of its proper divisors (1).

128756954605481 is an equidigital number, since it uses as much as digits as its factorization.

128756954605481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 580608000, while the sum is 71.

The spelling of 128756954605481 in words is "one hundred twenty-eight trillion, seven hundred fifty-six billion, nine hundred fifty-four million, six hundred five thousand, four hundred eighty-one".