28766778 has 8 divisors (see below), whose sum is σ = 57533568. Its totient is φ = 9588924.

The previous prime is 28766713. The next prime is 28766783. The reversal of 28766778 is 87766782.

It is a sphenic number, since it is the product of 3 distinct primes.

28766778 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 28766778.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2397226 + ... + 2397237.

It is an arithmetic number, because the mean of its divisors is an integer number (7191696).

Almost surely, 2^28766778 is an apocalyptic number.

28766778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28766778 is a wasteful number, since it uses less digits than its factorization.

28766778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4794468.

The product of its digits is 1580544, while the sum is 51.

The square root of 28766778 is about 5363.4669757536. The cubic root of 28766778 is about 306.4058649606.

The spelling of 28766778 in words is "twenty-eight million, seven hundred sixty-six thousand, seven hundred seventy-eight".