128685013 has 4 divisors (see below), whose sum is σ = 131423040. Its totient is φ = 125946988.

The previous prime is 128684987. The next prime is 128685017. The reversal of 128685013 is 310586821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 310586821 = 17 ⋅18269813.

It is a cyclic number.

It is not a de Polignac number, because 128685013 - 2¹⁷ = 128553941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128685013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128685017) 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 in 3 ways as a sum of consecutive naturals, for example, 1368943 + ... + 1369036.

It is an arithmetic number, because the mean of its divisors is an integer number (32855760).

Almost surely, 2^128685013 is an apocalyptic number.

It is an amenable number.

128685013 is a deficient number, since it is larger than the sum of its proper divisors (2738027).

128685013 is an equidigital number, since it uses as much as digits as its factorization.

128685013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2738026.

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 128685013 is about 11343.9416870857. The cubic root of 128685013 is about 504.8658441797.

The spelling of 128685013 in words is "one hundred twenty-eight million, six hundred eighty-five thousand, thirteen".