28111057 has 8 divisors (see below), whose sum is σ = 30770600. Its totient is φ = 25522560.

The previous prime is 28111049. The next prime is 28111067. The reversal of 28111057 is 75011182.

It can be written as a sum of positive squares in 4 ways, for example, as 904401 + 27206656 = 951^2 + 5216^2 .

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 28111057 - 2³ = 28111049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28111067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16932 + ... + 18517.

It is an arithmetic number, because the mean of its divisors is an integer number (3846325).

Almost surely, 2^28111057 is an apocalyptic number.

It is an amenable number.

28111057 is a deficient number, since it is larger than the sum of its proper divisors (2659543).

28111057 is a wasteful number, since it uses less digits than its factorization.

28111057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35523.

The product of its (nonzero) digits is 560, while the sum is 25.

The square root of 28111057 is about 5301.9861372886. The cubic root of 28111057 is about 304.0598371652.

The spelling of 28111057 in words is "twenty-eight million, one hundred eleven thousand, fifty-seven".