28217004 has 24 divisors (see below), whose sum is σ = 66425520. Its totient is φ = 9321984.

The previous prime is 28216973. The next prime is 28217011. The reversal of 28217004 is 40071282.

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, 9049 + ... + 11760.

It is an arithmetic number, because the mean of its divisors is an integer number (2767730).

Almost surely, 2^28217004 is an apocalyptic number.

It is an amenable number.

28217004 is an abundant number, since it is smaller than the sum of its proper divisors (38208516).

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

28217004 is a wasteful number, since it uses less digits than its factorization.

28217004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20929 (or 20927 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 28217004 is about 5311.9679968915. The cubic root of 28217004 is about 304.4413459033.

Adding to 28217004 its reverse (40071282), we get a palindrome (68288286).

The spelling of 28217004 in words is "twenty-eight million, two hundred seventeen thousand, four".