28205490 has 16 divisors (see below), whose sum is σ = 67693248. Its totient is φ = 7521456.

The previous prime is 28205477. The next prime is 28205501. The reversal of 28205490 is 9450282.

It is a super-2 number, since 2×28205490² = 1591099332280200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 940183 = 28205490 / (2 + 8 + 2 + 0 + 5 + 4 + 9 + 0).

It is an unprimeable number.

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, 470062 + ... + 470121.

It is an arithmetic number, because the mean of its divisors is an integer number (4230828).

Almost surely, 2^28205490 is an apocalyptic number.

28205490 is an abundant number, since it is smaller than the sum of its proper divisors (39487758).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28205490 is a wasteful number, since it uses less digits than its factorization.

28205490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 940193.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 28205490 is about 5310.8841071897. The cubic root of 28205490 is about 304.3999309873.

The spelling of 28205490 in words is "twenty-eight million, two hundred five thousand, four hundred ninety".