278440 has 16 divisors (see below), whose sum is σ = 626580. Its totient is φ = 111360.

The previous prime is 278437. The next prime is 278459. The reversal of 278440 is 44872.

It can be written as a sum of positive squares in 2 ways, for example, as 276676 + 1764 = 526^2 + 42^2 .

It is a plaindrome in base 15.

It is a nialpdrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3441 + ... + 3520.

2²⁷⁸⁴⁴⁰ is an apocalyptic number.

278440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

278440 is an abundant number, since it is smaller than the sum of its proper divisors (348140).

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

278440 is a wasteful number, since it uses less digits than its factorization.

278440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6972 (or 6968 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 278440 is about 527.6741418717. The cubic root of 278440 is about 65.2996031173.

The spelling of 278440 in words is "two hundred seventy-eight thousand, four hundred forty".