28057728205 has 16 divisors (see below), whose sum is σ = 36328857264. Its totient is φ = 20679759360.

The previous prime is 28057728187. The next prime is 28057728253. The reversal of 28057728205 is 50282775082.

It can be written as a sum of positive squares in 8 ways, for example, as 7364042596 + 20693685609 = 85814^2 + 143853^2 .

It is not a de Polignac number, because 28057728205 - 2⁵ = 28057728173 is a prime.

It is a super-2 number, since 2×28057728205² (a number of 22 digits) contains 22 as substring.

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 (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 380394 + ... + 448123.

It is an arithmetic number, because the mean of its divisors is an integer number (2270553579).

Almost surely, 2^28057728205 is an apocalyptic number.

It is an amenable number.

28057728205 is a deficient number, since it is larger than the sum of its proper divisors (8271129059).

28057728205 is a wasteful number, since it uses less digits than its factorization.

28057728205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829056.

The product of its (nonzero) digits is 627200, while the sum is 46.

The spelling of 28057728205 in words is "twenty-eight billion, fifty-seven million, seven hundred twenty-eight thousand, two hundred five".