278740 has 48 divisors (see below), whose sum is σ = 733824. Its totient is φ = 86400.

The previous prime is 278717. The next prime is 278741. The reversal of 278740 is 47872.

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 278699 and 278708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (278741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1450 + ... + 1630.

It is an arithmetic number, because the mean of its divisors is an integer number (15288).

2²⁷⁸⁷⁴⁰ is an apocalyptic number.

278740 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 278740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (366912).

278740 is an abundant number, since it is smaller than the sum of its proper divisors (455084).

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

278740 is a wasteful number, since it uses less digits than its factorization.

278740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 28.

The square root of 278740 is about 527.9583316892. The cubic root of 278740 is about 65.3230466474.

The spelling of 278740 in words is "two hundred seventy-eight thousand, seven hundred forty".