278720 has 56 divisors (see below), whose sum is σ = 725424. Its totient is φ = 101376.

The previous prime is 278717. The next prime is 278741. The reversal of 278720 is 27872.

278720 = 29³ + 30³ + ... + 36³.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 278720.

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, 4127 + ... + 4193.

It is an arithmetic number, because the mean of its divisors is an integer number (12954).

2²⁷⁸⁷²⁰ is an apocalyptic number.

278720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 278720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (362712).

278720 is an abundant number, since it is smaller than the sum of its proper divisors (446704).

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

278720 is a wasteful number, since it uses less digits than its factorization.

278720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 87 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 26.

The square root of 278720 is about 527.9393904607. The cubic root of 278720 is about 65.3214842688.

The spelling of 278720 in words is "two hundred seventy-eight thousand, seven hundred twenty".