28788778 has 16 divisors (see below), whose sum is σ = 45489600. Its totient is φ = 13637536.

The previous prime is 28788763. The next prime is 28788787. The reversal of 28788778 is 87788782.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1998 + ... + 7846.

It is an arithmetic number, because the mean of its divisors is an integer number (2843100).

Almost surely, 2^28788778 is an apocalyptic number.

28788778 is a deficient number, since it is larger than the sum of its proper divisors (16700822).

28788778 is a wasteful number, since it uses less digits than its factorization.

28788778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5981.

The product of its digits is 2809856, while the sum is 55.

The square root of 28788778 is about 5365.5174960110. The cubic root of 28788778 is about 306.4839551721.

The spelling of 28788778 in words is "twenty-eight million, seven hundred eighty-eight thousand, seven hundred seventy-eight".