278966 has 4 divisors (see below), whose sum is σ = 418452. Its totient is φ = 139482.

The previous prime is 278947. The next prime is 278981. The reversal of 278966 is 669872.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

278966 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69740 + ... + 69743.

It is an arithmetic number, because the mean of its divisors is an integer number (104613).

278966 is a Friedman number, since it can be written as 6^7-962-8, using all its digits and the basic arithmetic operations.

2²⁷⁸⁹⁶⁶ is an apocalyptic number.

278966 is a deficient number, since it is larger than the sum of its proper divisors (139486).

278966 is a wasteful number, since it uses less digits than its factorization.

278966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139485.

The product of its digits is 36288, while the sum is 38.

The square root of 278966 is about 528.1723203652. The cubic root of 278966 is about 65.3406963334.

The spelling of 278966 in words is "two hundred seventy-eight thousand, nine hundred sixty-six".