279999 has 12 divisors (see below), whose sum is σ = 412776. Its totient is φ = 182832.

The previous prime is 279991. The next prime is 280001. The reversal of 279999 is 999972.

It is not a de Polignac number, because 279999 - 2³ = 279991 is a prime.

279999 is a modest number, since divided by 999 gives 279 as remainder.

It is a plaindrome in base 10 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (279991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 184 + ... + 770.

It is an arithmetic number, because the mean of its divisors is an integer number (34398).

2²⁷⁹⁹⁹⁹ is an apocalyptic number.

279999 is a deficient number, since it is larger than the sum of its proper divisors (132777).

279999 is a wasteful number, since it uses less digits than its factorization.

279999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646 (or 643 counting only the distinct ones).

The product of its digits is 91854, while the sum is 45.

The square root of 279999 is about 529.1493173009. The cubic root of 279999 is about 65.4212483211.

The spelling of 279999 in words is "two hundred seventy-nine thousand, nine hundred ninety-nine".