28778800 has 30 divisors (see below), whose sum is σ = 69142028. Its totient is φ = 11511360.

The previous prime is 28778797. The next prime is 28778801. The reversal of 28778800 is 887782.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (28778801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35574 + ... + 36373.

Almost surely, 2^28778800 is an apocalyptic number.

28778800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28778800 is an abundant number, since it is smaller than the sum of its proper divisors (40363228).

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

28778800 is a wasteful number, since it uses less digits than its factorization.

28778800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71965 (or 71954 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 40.

The square root of 28778800 is about 5364.5875889951. The cubic root of 28778800 is about 306.4485426434.

The spelling of 28778800 in words is "twenty-eight million, seven hundred seventy-eight thousand, eight hundred".