278778 has 16 divisors (see below), whose sum is σ = 564480. Its totient is φ = 91776.

The previous prime is 278767. The next prime is 278801. The reversal of 278778 is 877872.

It is a congruent number.

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, 343 + ... + 821.

It is an arithmetic number, because the mean of its divisors is an integer number (35280).

2²⁷⁸⁷⁷⁸ is an apocalyptic number.

278778 is an abundant number, since it is smaller than the sum of its proper divisors (285702).

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

278778 is a wasteful number, since it uses less digits than its factorization.

278778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 581.

The product of its digits is 43904, while the sum is 39.

The square root of 278778 is about 527.9943181512. The cubic root of 278778 is about 65.3260149607.

The spelling of 278778 in words is "two hundred seventy-eight thousand, seven hundred seventy-eight".