28217100 has 36 divisors (see below), whose sum is σ = 81642344. Its totient is φ = 7524480.

The previous prime is 28217089. The next prime is 28217131. The reversal of 28217100 is 171282.

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 11 ways as a sum of consecutive naturals, for example, 46729 + ... + 47328.

Almost surely, 2^28217100 is an apocalyptic number.

28217100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28217100 is an abundant number, since it is smaller than the sum of its proper divisors (53425244).

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

28217100 is a wasteful number, since it uses less digits than its factorization.

28217100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94074 (or 94067 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 21.

The square root of 28217100 is about 5311.9770330829. The cubic root of 28217100 is about 304.4416911601.

Adding to 28217100 its reverse (171282), we get a palindrome (28388382).

The spelling of 28217100 in words is "twenty-eight million, two hundred seventeen thousand, one hundred".