28571081785 has 8 divisors (see below), whose sum is σ = 34293570696. Its totient is φ = 22851350400.

The previous prime is 28571081767. The next prime is 28571081797. The reversal of 28571081785 is 58718017582.

It can be written as a sum of positive squares in 4 ways, for example, as 1756364281 + 26814717504 = 41909^2 + 163752^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28571081785 - 2²³ = 28562693177 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 666516 + ... + 708085.

It is an arithmetic number, because the mean of its divisors is an integer number (4286696337).

Almost surely, 2^28571081785 is an apocalyptic number.

It is an amenable number.

28571081785 is a deficient number, since it is larger than the sum of its proper divisors (5722488911).

28571081785 is a wasteful number, since it uses less digits than its factorization.

28571081785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378763.

The product of its (nonzero) digits is 1254400, while the sum is 52.

The spelling of 28571081785 in words is "twenty-eight billion, five hundred seventy-one million, eighty-one thousand, seven hundred eighty-five".