28188898 has 16 divisors (see below), whose sum is σ = 43524216. Its totient is φ = 13686400.

The previous prime is 28188887. The next prime is 28188911. The reversal of 28188898 is 89888182.

It can be written as a sum of positive squares in 4 ways, for example, as 27384289 + 804609 = 5233^2 + 897^2 .

It is a super-2 number, since 2×28188898² = 1589227940908808, which contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 9390 + ... + 12022.

Almost surely, 2^28188898 is an apocalyptic number.

28188898 is a deficient number, since it is larger than the sum of its proper divisors (15335318).

28188898 is a wasteful number, since it uses less digits than its factorization.

28188898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2789.

The product of its digits is 589824, while the sum is 52.

The square root of 28188898 is about 5309.3218022644. The cubic root of 28188898 is about 304.3402310929.

The spelling of 28188898 in words is "twenty-eight million, one hundred eighty-eight thousand, eight hundred ninety-eight".