28868778 has 16 divisors (see below), whose sum is σ = 64152960. Its totient is φ = 9622908.

The previous prime is 28868773. The next prime is 28868779. The reversal of 28868778 is 87786882.

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 534607 = 28868778 / (2 + 8 + 8 + 6 + 8 + 7 + 7 + 8).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28868773) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 267250 + ... + 267357.

It is an arithmetic number, because the mean of its divisors is an integer number (4009560).

Almost surely, 2^28868778 is an apocalyptic number.

28868778 is an abundant number, since it is smaller than the sum of its proper divisors (35284182).

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

28868778 is a wasteful number, since it uses less digits than its factorization.

28868778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 534618 (or 534612 counting only the distinct ones).

The product of its digits is 2408448, while the sum is 54.

The square root of 28868778 is about 5372.9673365841. The cubic root of 28868778 is about 306.7675846711.

It can be divided in two parts, 28868 and 778, that added together give a triangular number (29646 = T₂₄₃).

The spelling of 28868778 in words is "twenty-eight million, eight hundred sixty-eight thousand, seven hundred seventy-eight".