28580778 has 48 divisors (see below), whose sum is σ = 63648000. Its totient is φ = 9266400.

The previous prime is 28580771. The next prime is 28580819. The reversal of 28580778 is 87708582.

It is a happy number.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (28580771) 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 23 ways as a sum of consecutive naturals, for example, 143523 + ... + 143721.

It is an arithmetic number, because the mean of its divisors is an integer number (1326000).

Almost surely, 2^28580778 is an apocalyptic number.

28580778 is an abundant number, since it is smaller than the sum of its proper divisors (35067222).

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

28580778 is a wasteful number, since it uses less digits than its factorization.

28580778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 250880, while the sum is 45.

The square root of 28580778 is about 5346.0993256766. The cubic root of 28580778 is about 305.7440510014.

The spelling of 28580778 in words is "twenty-eight million, five hundred eighty thousand, seven hundred seventy-eight".