128918513 has 2 divisors, whose sum is σ = 128918514. Its totient is φ = 128918512.

The previous prime is 128918501. The next prime is 128918557. The reversal of 128918513 is 315819821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 82228624 + 46689889 = 9068^2 + 6833^2 .

It is a cyclic number.

It is not a de Polignac number, because 128918513 - 2¹⁸ = 128656369 is a prime.

It is not a weakly prime, because it can be changed into another prime (128918563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64459256 + 64459257.

It is an arithmetic number, because the mean of its divisors is an integer number (64459257).

Almost surely, 2^128918513 is an apocalyptic number.

It is an amenable number.

128918513 is a deficient number, since it is larger than the sum of its proper divisors (1).

128918513 is an equidigital number, since it uses as much as digits as its factorization.

128918513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 38.

The square root of 128918513 is about 11354.2288597685. The cubic root of 128918513 is about 505.1710207289.

The spelling of 128918513 in words is "one hundred twenty-eight million, nine hundred eighteen thousand, five hundred thirteen".