279987 has 4 divisors (see below), whose sum is σ = 373320. Its totient is φ = 186656.

The previous prime is 279977. The next prime is 279991. The reversal of 279987 is 789972.

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 279987 - 2⁸ = 279731 is a prime.

It is a D-number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 279987.

It is not an unprimeable number, because it can be changed into a prime (279967) 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, 46662 + ... + 46667.

It is an arithmetic number, because the mean of its divisors is an integer number (93330).

2²⁷⁹⁹⁸⁷ is an apocalyptic number.

279987 is a deficient number, since it is larger than the sum of its proper divisors (93333).

279987 is an equidigital number, since it uses as much as digits as its factorization.

279987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93332.

The product of its digits is 63504, while the sum is 42.

The square root of 279987 is about 529.1379782250. The cubic root of 279987 is about 65.4203137152.

The spelling of 279987 in words is "two hundred seventy-nine thousand, nine hundred eighty-seven".