278820828 has 144 divisors (see below), whose sum is σ = 848850912. Its totient is φ = 76032000.

The previous prime is 278820809. The next prime is 278820847. The reversal of 278820828 is 828028872.

278820828 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (278820809) and next prime (278820847).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 210408 + ... + 211728.

It is an arithmetic number, because the mean of its divisors is an integer number (5894798).

Almost surely, 2^278820828 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 278820828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (424425456).

278820828 is an abundant number, since it is smaller than the sum of its proper divisors (570030084).

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

278820828 is a wasteful number, since it uses less digits than its factorization.

278820828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1396 (or 1391 counting only the distinct ones).

The product of its (nonzero) digits is 229376, while the sum is 45.

The square root of 278820828 is about 16697.9288536034. The cubic root of 278820828 is about 653.2936008277.

The spelling of 278820828 in words is "two hundred seventy-eight million, eight hundred twenty thousand, eight hundred twenty-eight".