28209085 has 8 divisors (see below), whose sum is σ = 33892920. Its totient is φ = 22539264.

The previous prime is 28209061. The next prime is 28209119. The reversal of 28209085 is 58090282.

It can be written as a sum of positive squares in 4 ways, for example, as 1552516 + 26656569 = 1246^2 + 5163^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28209085 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28209085.

It is a congruent 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, 1609 + ... + 7681.

It is an arithmetic number, because the mean of its divisors is an integer number (4236615).

Almost surely, 2^28209085 is an apocalyptic number.

It is an amenable number.

28209085 is a deficient number, since it is larger than the sum of its proper divisors (5683835).

28209085 is an equidigital number, since it uses as much as digits as its factorization.

28209085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7007.

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 28209085 is about 5311.2225522943. Note that the first 3 decimals coincide. The cubic root of 28209085 is about 304.4128631182.

The spelling of 28209085 in words is "twenty-eight million, two hundred nine thousand, eighty-five".