28157585905 has 8 divisors (see below), whose sum is σ = 33790401000. Its totient is φ = 22525203456.

The previous prime is 28157585903. The next prime is 28157586053. The reversal of 28157585905 is 50958575182.

It can be written as a sum of positive squares in 4 ways, for example, as 3204012816 + 24953573089 = 56604^2 + 157967^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28157585905 - 2¹ = 28157585903 is a prime.

It is a super-3 number, since 3×28157585905³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (28157585903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58321 + ... + 244369.

It is an arithmetic number, because the mean of its divisors is an integer number (4223800125).

Almost surely, 2^28157585905 is an apocalyptic number.

It is an amenable number.

28157585905 is a deficient number, since it is larger than the sum of its proper divisors (5632815095).

28157585905 is a wasteful number, since it uses less digits than its factorization.

28157585905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216323.

The product of its (nonzero) digits is 5040000, while the sum is 55.

The spelling of 28157585905 in words is "twenty-eight billion, one hundred fifty-seven million, five hundred eighty-five thousand, nine hundred five".