28985857 has 4 divisors (see below), whose sum is σ = 29113776. Its totient is φ = 28857940.

The previous prime is 28985783. The next prime is 28985861. The reversal of 28985857 is 75858982.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28985857 - 2¹⁹ = 28461569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28985657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63619 + ... + 64072.

It is an arithmetic number, because the mean of its divisors is an integer number (7278444).

Almost surely, 2^28985857 is an apocalyptic number.

It is an amenable number.

28985857 is a deficient number, since it is larger than the sum of its proper divisors (127919).

28985857 is a wasteful number, since it uses less digits than its factorization.

28985857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127918.

The product of its digits is 1612800, while the sum is 52.

The square root of 28985857 is about 5383.8515024098. The cubic root of 28985857 is about 307.1817298761.

The spelling of 28985857 in words is "twenty-eight million, nine hundred eighty-five thousand, eight hundred fifty-seven".