278567 has 4 divisors (see below), whose sum is σ = 280440. Its totient is φ = 276696.

The previous prime is 278563. The next prime is 278581. The reversal of 278567 is 765872.

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

It is a cyclic number.

It is not a de Polignac number, because 278567 - 2² = 278563 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (278561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 692 + ... + 1017.

It is an arithmetic number, because the mean of its divisors is an integer number (70110).

2²⁷⁸⁵⁶⁷ is an apocalyptic number.

278567 is a deficient number, since it is larger than the sum of its proper divisors (1873).

278567 is a wasteful number, since it uses less digits than its factorization.

278567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1872.

The product of its digits is 23520, while the sum is 35.

The square root of 278567 is about 527.7944675724. The cubic root of 278567 is about 65.3095295994.

The spelling of 278567 in words is "two hundred seventy-eight thousand, five hundred sixty-seven".