2128402585 has 4 divisors (see below), whose sum is σ = 2554083108. Its totient is φ = 1702722064.

The previous prime is 2128402547. The next prime is 2128402603. The reversal of 2128402585 is 5852048212.

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 398840841 + 1729561744 = 19971^2 + 41588^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2128402585 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 212840254 + ... + 212840263.

It is an arithmetic number, because the mean of its divisors is an integer number (638520777).

Almost surely, 2^2128402585 is an apocalyptic number.

It is an amenable number.

2128402585 is a deficient number, since it is larger than the sum of its proper divisors (425680523).

2128402585 is an equidigital number, since it uses as much as digits as its factorization.

2128402585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 425680522.

The product of its (nonzero) digits is 51200, while the sum is 37.

The square root of 2128402585 is about 46134.6137406611. The cubic root of 2128402585 is about 1286.3266258105.

The spelling of 2128402585 in words is "two billion, one hundred twenty-eight million, four hundred two thousand, five hundred eighty-five".