28216864 has 24 divisors (see below), whose sum is σ = 59826060. Its totient is φ = 13022976.

The previous prime is 28216847. The next prime is 28216879. The reversal of 28216864 is 46861282.

It can be written as a sum of positive squares in 2 ways, for example, as 28005264 + 211600 = 5292^2 + 460^2 .

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 33499 + ... + 34330.

Almost surely, 2^28216864 is an apocalyptic number.

It is an amenable number.

28216864 is an abundant number, since it is smaller than the sum of its proper divisors (31609196).

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

28216864 is a wasteful number, since it uses less digits than its factorization.

28216864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67852 (or 67844 counting only the distinct ones).

The product of its digits is 36864, while the sum is 37.

The square root of 28216864 is about 5311.9548190850. The cubic root of 28216864 is about 304.4408424025.

The spelling of 28216864 in words is "twenty-eight million, two hundred sixteen thousand, eight hundred sixty-four".