28307828 has 12 divisors (see below), whose sum is σ = 51247140. Its totient is φ = 13665792.

The previous prime is 28307827. The next prime is 28307831. The reversal of 28307828 is 82870382.

It can be written as a sum of positive squares in 2 ways, for example, as 6666724 + 21641104 = 2582^2 + 4652^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28307791 and 28307800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28307827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121901 + ... + 122132.

It is an arithmetic number, because the mean of its divisors is an integer number (4270595).

Almost surely, 2^28307828 is an apocalyptic number.

It is an amenable number.

28307828 is a deficient number, since it is larger than the sum of its proper divisors (22939312).

28307828 is a wasteful number, since it uses less digits than its factorization.

28307828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244066 (or 244064 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 28307828 is about 5320.5101259184. The cubic root of 28307828 is about 304.7676381253.

The spelling of 28307828 in words is "twenty-eight million, three hundred seven thousand, eight hundred twenty-eight".