28209478 has 16 divisors (see below), whose sum is σ = 46748160. Its totient is φ = 12659400.

The previous prime is 28209451. The next prime is 28209487. The reversal of 28209478 is 87490282.

It is a self number, because there is not a number n which added to its sum of digits gives 28209478.

It is a congruent number.

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, 6378 + ... + 9853.

It is an arithmetic number, because the mean of its divisors is an integer number (2921760).

Almost surely, 2^28209478 is an apocalyptic number.

28209478 is a deficient number, since it is larger than the sum of its proper divisors (18538682).

28209478 is a wasteful number, since it uses less digits than its factorization.

28209478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16323.

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 28209478 is about 5311.2595492971. The cubic root of 28209478 is about 304.4142767727.

The spelling of 28209478 in words is "twenty-eight million, two hundred nine thousand, four hundred seventy-eight".