28855813 has 16 divisors (see below), whose sum is σ = 34867840. Its totient is φ = 23392800.

The previous prime is 28855811. The next prime is 28855829. The reversal of 28855813 is 31855882.

It is not a de Polignac number, because 28855813 - 2¹ = 28855811 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28855811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47713 + ... + 48313.

It is an arithmetic number, because the mean of its divisors is an integer number (2179240).

Almost surely, 2^28855813 is an apocalyptic number.

It is an amenable number.

28855813 is a deficient number, since it is larger than the sum of its proper divisors (6012027).

28855813 is an frugal number, since it uses more digits than its factorization.

28855813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 665 (or 627 counting only the distinct ones).

The product of its digits is 76800, while the sum is 40.

The square root of 28855813 is about 5371.7606983186. The cubic root of 28855813 is about 306.7216545746.

The spelling of 28855813 in words is "twenty-eight million, eight hundred fifty-five thousand, eight hundred thirteen".