28856538 has 48 divisors (see below), whose sum is σ = 65198952. Its totient is φ = 9216000.

The previous prime is 28856533. The next prime is 28856557. The reversal of 28856538 is 83565882.

It is a happy number.

28856538 is a `hidden beast` number, since 2 + 88 + 565 + 3 + 8 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 15657849 + 13198689 = 3957^2 + 3633^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28856493 and 28856502.

It is not an unprimeable number, because it can be changed into a prime (28856533) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 44698 + ... + 45338.

Almost surely, 2^28856538 is an apocalyptic number.

28856538 is an abundant number, since it is smaller than the sum of its proper divisors (36342414).

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

28856538 is a wasteful number, since it uses less digits than its factorization.

28856538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 751 (or 748 counting only the distinct ones).

The product of its digits is 460800, while the sum is 45.

The square root of 28856538 is about 5371.8281804242. The cubic root of 28856538 is about 306.7242233388.

The spelling of 28856538 in words is "twenty-eight million, eight hundred fifty-six thousand, five hundred thirty-eight".