279921 has 4 divisors (see below), whose sum is σ = 373232. Its totient is φ = 186612.

The previous prime is 279919. The next prime is 279941. The reversal of 279921 is 129972.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 279921 - 2¹ = 279919 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 6.

It is a zygodrome in base 6.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 279921.

It is not an unprimeable number, because it can be changed into a prime (279941) 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, 46651 + ... + 46656.

It is an arithmetic number, because the mean of its divisors is an integer number (93308).

2²⁷⁹⁹²¹ is an apocalyptic number.

It is an amenable number.

279921 is a deficient number, since it is larger than the sum of its proper divisors (93311).

279921 is an equidigital number, since it uses as much as digits as its factorization.

279921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93310.

The product of its digits is 2268, while the sum is 30.

The square root of 279921 is about 529.0756089634. The cubic root of 279921 is about 65.4151729051.

The spelling of 279921 in words is "two hundred seventy-nine thousand, nine hundred twenty-one".