28518228 has 36 divisors (see below), whose sum is σ = 72797088. Its totient is φ = 9412560.

The previous prime is 28518227. The next prime is 28518239. The reversal of 28518228 is 82281582.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28518192 and 28518201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28518227) by changing a digit.

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, 138 + ... + 7553.

Almost surely, 2^28518228 is an apocalyptic number.

It is an amenable number.

28518228 is an abundant number, since it is smaller than the sum of its proper divisors (44278860).

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

28518228 is a wasteful number, since it uses less digits than its factorization.

28518228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7804 (or 7799 counting only the distinct ones).

The product of its digits is 20480, while the sum is 36.

The square root of 28518228 is about 5340.2460617466. The cubic root of 28518228 is about 305.5208443557.

The spelling of 28518228 in words is "twenty-eight million, five hundred eighteen thousand, two hundred twenty-eight".