278438256 has 80 divisors (see below), whose sum is σ = 814367520. Its totient is φ = 91054080.

The previous prime is 278438243. The next prime is 278438261. The reversal of 278438256 is 652834872.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16816 + ... + 28976.

It is an arithmetic number, because the mean of its divisors is an integer number (10179594).

Almost surely, 2^278438256 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 278438256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (407183760).

278438256 is an abundant number, since it is smaller than the sum of its proper divisors (535929264).

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

278438256 is a wasteful number, since it uses less digits than its factorization.

278438256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12231 (or 12219 counting only the distinct ones).

The product of its digits is 645120, while the sum is 45.

The square root of 278438256 is about 16686.4692490652. The cubic root of 278438256 is about 652.9946678301.

The spelling of 278438256 in words is "two hundred seventy-eight million, four hundred thirty-eight thousand, two hundred fifty-six".