128199565 has 16 divisors (see below), whose sum is σ = 167389488. Its totient is φ = 93689856.

The previous prime is 128199557. The next prime is 128199571. The reversal of 128199565 is 565991821.

It can be written as a sum of positive squares in 8 ways, for example, as 11881 + 128187684 = 109^2 + 11322^2 .

It is not a de Polignac number, because 128199565 - 2³ = 128199557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3862 + ... + 16471.

It is an arithmetic number, because the mean of its divisors is an integer number (10461843).

Almost surely, 2^128199565 is an apocalyptic number.

It is an amenable number.

128199565 is a deficient number, since it is larger than the sum of its proper divisors (39189923).

128199565 is a wasteful number, since it uses less digits than its factorization.

128199565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20448.

The product of its digits is 194400, while the sum is 46.

The square root of 128199565 is about 11322.5246742942. The cubic root of 128199565 is about 504.2301966099.

The spelling of 128199565 in words is "one hundred twenty-eight million, one hundred ninety-nine thousand, five hundred sixty-five".