28121828 has 24 divisors (see below), whose sum is σ = 57554112. Its totient is φ = 11771424.

The previous prime is 28121827. The next prime is 28121857. The reversal of 28121828 is 82812182.

It is a junction number, because it is equal to n+sod(n) for n = 28121794 and 28121803.

It is not an unprimeable number, because it can be changed into a prime (28121827) 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 7 ways as a sum of consecutive naturals, for example, 10475 + ... + 12882.

It is an arithmetic number, because the mean of its divisors is an integer number (2398088).

Almost surely, 2^28121828 is an apocalyptic number.

28121828 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28121828 is an abundant number, since it is smaller than the sum of its proper divisors (29432284).

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

28121828 is a wasteful number, since it uses less digits than its factorization.

28121828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23411 (or 23409 counting only the distinct ones).

The product of its digits is 4096, while the sum is 32.

The square root of 28121828 is about 5303.0017914385. The cubic root of 28121828 is about 304.0986666112.

The spelling of 28121828 in words is "twenty-eight million, one hundred twenty-one thousand, eight hundred twenty-eight".