128511605 has 4 divisors (see below), whose sum is σ = 154213932. Its totient is φ = 102809280.

The previous prime is 128511577. The next prime is 128511631. The reversal of 128511605 is 506115821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24512401 + 103999204 = 4951^2 + 10198^2 .

It is not a de Polignac number, because 128511605 - 2⁶ = 128511541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 12851156 + ... + 12851165.

It is an arithmetic number, because the mean of its divisors is an integer number (38553483).

Almost surely, 2^128511605 is an apocalyptic number.

It is an amenable number.

128511605 is a deficient number, since it is larger than the sum of its proper divisors (25702327).

128511605 is an equidigital number, since it uses as much as digits as its factorization.

128511605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25702326.

The product of its (nonzero) digits is 2400, while the sum is 29.

The square root of 128511605 is about 11336.2959118047. The cubic root of 128511605 is about 504.6389668653.

The spelling of 128511605 in words is "one hundred twenty-eight million, five hundred eleven thousand, six hundred five".