28918778 has 8 divisors (see below), whose sum is σ = 49575072. Its totient is φ = 12393756.

The previous prime is 28918759. The next prime is 28918787. The reversal of 28918778 is 87781982.

It is a happy number.

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

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, 1032800 + ... + 1032827.

It is an arithmetic number, because the mean of its divisors is an integer number (6196884).

Almost surely, 2^28918778 is an apocalyptic number.

28918778 is a deficient number, since it is larger than the sum of its proper divisors (20656294).

28918778 is a wasteful number, since it uses less digits than its factorization.

28918778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2065636.

The product of its digits is 451584, while the sum is 50.

The square root of 28918778 is about 5377.6182460268. The cubic root of 28918778 is about 306.9445871120.

The spelling of 28918778 in words is "twenty-eight million, nine hundred eighteen thousand, seven hundred seventy-eight".