278668 has 24 divisors (see below), whose sum is σ = 550368. Its totient is φ = 122496.

The previous prime is 278651. The next prime is 278671. The reversal of 278668 is 866872.

It is a zygodrome in base 6.

It is a congruent number.

It is an unprimeable number.

278668 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1080 + ... + 1312.

It is an arithmetic number, because the mean of its divisors is an integer number (22932).

2²⁷⁸⁶⁶⁸ is an apocalyptic number.

It is an amenable number.

278668 is a deficient number, since it is larger than the sum of its proper divisors (271700).

278668 is a wasteful number, since it uses less digits than its factorization.

278668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273 (or 271 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 278668 is about 527.8901400860. The cubic root of 278668 is about 65.3174217348.

Subtracting from 278668 its sum of digits (37), we obtain a triangular number (278631 = T₇₄₆).

It can be divided in two parts, 278 and 668, that added together give a triangular number (946 = T₄₃).

The spelling of 278668 in words is "two hundred seventy-eight thousand, six hundred sixty-eight".